What is Jo's primary conflict with her mother, Helen, in 'A Taste of Honey'?

Lack of support and understanding

A taste of honey | Quizalize

Broken windows are covered. Floorboards are patched and doors screwed back on. The road that was ruined by German tanks is shovelled and raked smooth. Boot-shaped bruises turn yellow then fade and disappear. Flowers grow and spread across the ugly German footprints stomped into garden beds. The village looks pretty once more. School stops for the summer and everyone is put to work on the kolkhoz, the village farm. Women and big boys begin harvesting the barley crops in the outer fields. The biggest girls milk the cows, morning and night, and keep the barns clean. Old Nikolay mends ploughs, horse harnesses, pitchforks and scythes in his workshop. Anna Pushinka teaches Yelena and her friends how to get the honey from the beehives that are scattered through the orchards. I am in charge of collecting eggs. My friends Olga and Nina help. Olga and Nina are five, a year younger than me. They are twins and look exactly alike, except Nina’s nose is a little bit crooked from when she fell out of bed and squashed it sideways on the floor. The hens, ducks and geese wander free in the summer, so collecting eggs is like a treasure hunt and takes hours. Catching the hens for their daily hugs takes even longer, but I think it’s important because hugs make everyone happy and happy hens lay bigger eggs. Olga says I’m the best hen-hugger in all of Russia. Nina says I’ll be the best cow-hugger, too, when my arms grow longer. But good hugs have nothing to do with the size of your arms. It’s all to do with the size of your heart. When we are done with the hens, Olga, Nina and I can spend the rest of the day doing whatever we like. We climb the apricot trees, chase squirrels, lie in the meadow marvelling at how hot Ushanka’s black fur becomes in the sunshine, make daisy chains and race little boats of bark in the stream. I teach Olga and Nina the alphabet and we use charcoal to write our letters and our names all over the village – on doors and walls and the freshly cut ends of firewood. In between, I practise my knots. In case the German princemonsters return. I slip into Old Nikolay’s workshop and tie knots in the harnesses hanging on the walls. I wander into gardens where the washing is hung out to dry and tie knots in the laces on pants and smocks. I creep up behind Anna Pushinka and tie knots in her apron strings. I find baling twine in the hay shed and tie my own ankles together. I do such a good job of these last knots that I can’t get them undone. I have to jump all the way to Olga and Nina’s house and ask them to cut me free with their mama’s knife. At the end of each day, Ushanka and I run out into the distant barley fields to meet Mama. This is my favourite part of the day, because Mama always shouts, ‘Little Rabbit!’ and smothers my head with kisses. And as we walk home, we sing. Everyone – women, big boys and me. I love to sing. Almost as much as I love to be kissed by Mama. Sometimes one of the boys, Mikhail, has his balalaika with him. He takes the instrument out from beneath the sheaves of barley piled high on the wagon and plays music. We sing about forests and orchards and people who find their true love. As we walk home, arm in arm, my heart fills with happiness and my belly swells with pride that I am allowed to sing along with the big boys. And I can almost forget about the German prince-monsters and their lies about Russia and their big ugly boots. Almost. But today, when Mikhail reaches for his balalaika, I see other things hiding beneath the barley sheaves. Three of the mamas rush forward and cover them up, but it’s too late. I know they are there. I’ve already seen them. Rifles. Lots of rifles. Mikhail hugs his balalaika to his chest and blushes. ‘So play!’ cries Mama, her voice oddly loud and high. ‘Let’s play Sasha’s favourite song, “The Little Birch Tree”.’ So Mikhail plays and everyone sings about the lovely birch tree with its curly leaves and the branches that will be turned into silver flutes. They sing too quickly, too loudly, and as they sing and walk, they cast nervous sideways glances at me. ‘It’s alright,’ I say, when the song comes to an end. ‘I didn’t see the rifles.’ Mama nods and smiles, and I know it was the right thing to say. But I did see the rifles. And I think about Yelena wanting to get lots of guns and dynamite for the Partisans so they can shoot the Germans and blow them into thousands of tiny pieces, and Mama looking as though she agreed, and I know this is what the mamas and the big boys are doing. As well as harvesting, they are helping the Partisans. Three days later, I wake before dawn and I am all alone. Yelena is always here beside me when I wake. But not this morning. I climb down from our bed above the stove. Mama is filling a cloth sack with bread. She ties it closed with a piece of string and hands it to Yelena. ‘Stay out of sight,’ says Mama. ‘And don’t return until after dark.’ ‘Where’s she going?’ I ask. ‘Nowhere,’ snaps Mama. ‘Then why does she need all that bread?’ I ask. ‘There’s nothing left for us.’ Mama baked four loaves last night and she has stuffed them all into the sack. Yelena opens her mouth, but before she can speak, Mama shoves her out the door and sends her on the way to nowhere. Mama turns and stares at me, her blue, blue cornflower eyes wide with worry. ‘I know,’ I say, flopping down on the bench. ‘I didn’t see any bread.’ Mama sits beside me and takes my hand. ‘And . . .?’ she prods, obviously waiting for more. I puzzle for a while, then say, ‘And I don’t have a sister called Yelena.’ Mama laughs, softly and with a little bit of sadness around the edges. ‘Sweet Little Rabbit! You do have a sister called Yelena.’ ‘I do?’ I ask, now confused. ‘I haven’t seen the rifles or the bread, but I have seen Yelena?’ ‘Yes.’ Mama smiles and the magic makes me smile, too. And I am glad that Yelena is real because I love her very much. ‘Yelena is real,’ Mama explains, ‘but she does not carry sacks of bread into the forest for the Partisans.’ ‘Of course not!’ I shout, slapping my forehead. ‘Because there is no bread!’ Mama laughs loudly now, with not a hint of sadness. She hugs me, pressing me against her warm, loving heart, covering my head with kisses. ‘Clever Little Rabbit,’ she murmurs, and then, in barely a whisper, ‘Your papa would be so proud.’ When I wake the next morning, Yelena is sleeping beside me, her mouth open, her braided hair unravelling. Mama is serving kasha to a strange woman seated at our table. I crawl down from above the stove and slide along the bench beside her. I stare at her pants, her tunic, the rope she is using as a belt and her big boots. She’s dressed like a man! And there’s a rifle leaning against the wall near the door. ‘Hello,’ I say. ‘I’m Sasha.’ The woman doesn’t reply. She just shovels down her kasha. I line my four wooden bears along the table in front of her bowl and say, ‘These are my bears: Big Bear, Medium Bear, Little Bear and Even Littler Bear.’ ‘Hello, Sasha. Hello, bears.’ She smiles but she doesn’t tell me her name. ‘Why are you dressed like a man?’ I ask, tugging at the sleeve of her tunic. ‘Because men’s clothes make it easier to run and climb and crawl and shoot,’ she says. ‘You’re a Partisan!’ I gasp. ‘But she’s not real,’ says Mama, placing a bowl of kasha before me. ‘Is the kasha real?’ I ask. Mama laughs. ‘Yes, Little Rabbit.’ I’m glad the food is real, because I’m hungry. But I’m disappointed that the woman is not real. I was going to ask if I could use her rope-belt to tie her ankles together. For practice. But if she’s not real, then the rope and her ankles aren’t either. The woman finishes her kasha, hangs her rifle over her shoulder, kisses Mama on the cheek then slips out the door. I run to the window to watch her leave, but by the time I get there, she’s gone. Vanished. ‘Because she’s not real,’ I whisper. A week later, Mama and I are working in the garden. We sing as we weed between the flowers and pluck caterpillars from the vegetables. Anna Pushinka is picking strawberries in her garden and wanders over. ‘Taste these,’ she says, holding out the basket. Mama reaches in and takes out a fat strawberry and a tiny piece of folded paper. The strawberry goes into her mouth, the paper into her pocket. ‘What’s on the paper?’ I ask. ‘Paper?’ Anna Pushinka replies with a wave of her hand. ‘Goodness, Sasha! Who has money for paper? These are lean times. We must choose between paper for writing and noodles for our soup. And I always choose noodles.’ She chuckles and I know the paper is yet another thing that is not real. That night, Mama slips the paper to Yelena, but she drops it on the floor. I pick it up for her, and I see that there are tiny words and numbers written all over it. I wish I could read better. I’m desperate to know what it says. Or rather, what it doesn’t say, because it’s not real. Later, when Mama has tucked us into our bed above the stove and Ushanka has wrapped herself around the top of my head, I ask Yelena, ‘What’s on the paper?’ ‘What paper?’ says Yelena. ‘The paper that isn’t real,’ I reply. Yelena stares at me, nibbling her lip, then whispers, ‘A message for the Partisans. Stuff about where the Germans have their headquarters and when their trains are travelling and where they store their ammunition.’ ‘Why?’ ‘So the Partisans can blow them up.’ Yelena grabs my arm. ‘But don’t tell anyone. It’s a secret.’ ‘What’s a secret?’ I ask. ‘The message.’ ‘What message?’ I say, my eyes wide. Yelena laughs. ‘Good boy, Sasha.’ My belly swells with pride. I know how to play this game. ‘How are your knots coming along?’ asks Yelena. ‘Good! Yesterday, I crept into the dairy and tied knots in the apron strings of all the girls who were milking and only one of them noticed. Today, I tied Olga’s ankles together with Mama’s embroidery thread and just now, while you were taking a bath, I tied the sleeves of your blouse together in an enormous knot.’ Yelena rolls her eyes, then says, ‘I’ll see if I can find you some rope for practising.’ ‘Practising what?’ I ask. ‘Your knots,’ she says. ‘What knots?’ Yelena, my big sister who is twelve and always serious t

Not long ago, I grabbed breakfast at a hotel in southern Spain. The only cereal available was a local version of frosted corn flakes, so I readied myself to enjoy a bowl of my childhood favorite. But my sweet indulgence wasn't what I'd expected: The cereal milk was heated — apparently standard in this part of Spain — and my poor frosted flakes immediately turned to mush. Not so grrrrrrreat. Soggy flakes or not, I find breakfast to be a fun part of my travel day, especially because the experience varies so much from one country's breakfast table to the next. The farther north you go in Europe, the heartier the breakfasts. The heaviest is the traditional British "fry." Also known as a "Plate of Cardiac Arrest," the fry is a fundamental part of the bed-and-breakfast experience, and is generally included in your room price. A standard fry comes with cereal or porridge, a fried egg, Canadian-style bacon or sausage (and sometimes mackerel or haggis), a grilled tomato, sautéed mushrooms, baked beans, and fried bread or toast. This protein-stuffed meal can tide me over until dinner. You'll quickly figure out which parts of the fry you like. Your host will likely ask you up front which breakfast items you actually like, rather than serve you the whole shebang and risk having to throw out uneaten food. The Scandinavian breakfasts buffet is the perennial favorite for the "most food on the table" award. It pays to take advantage of breakfast smorgasbords when you can. For about $20 (a cheap meal in these parts), you can dig into an all-you-can-eat extravaganza of fresh bread, cheeses, yogurt, cereal, boiled eggs, herring, cold cuts, and coffee or tea. In place of cereal and milk, Scandinavians like to pour thick yogurt over their granola. Throughout the Netherlands, Belgium, Germany, Austria, Switzerland, and most points east of there, expect a more modest buffet — but still plenty of options (rolls, bread, jam, cold cuts, cheeses, fruit, yogurt, and cereal). In these countries, there's a good chance of finding hard-boiled eggs, but scrambled or fried eggs are relatively rare. In Poland, track down jajecznica, the local wake-up call of eggs scrambled with kielbasa sausage, served with a side of potato pancakes. The breakfast of choice in Russia is oladi, pancakes perfectly fried to be crisp on the outside but soft in the middle, then topped with sour cream, honey, or berries. Germans have an endearing habit of greeting others in the breakfast room with a slow and dour "Morgen" ("Morning" — short for "good morning"), though they have plenty to be happy about. Breakfast is usually included, and offers hearty fuel for the day: ham, eggs, cheese, bread, rolls, and pots of coffee. In Switzerland, don't miss an opportunity to try Bircher Muesli, a healthful mix of oats, nuts, yogurt, and fruit that tastes far more delicious than it looks. If breakfast is optional, take a walk to the nearest bakery — every German, Austrian, and Swiss town has at least a few bakeries offering a world of enticing varieties of bread and pastries, baked fresh every morning. As you move south and west (France, Italy, Spain, and Portugal), skimpier "continental" breakfasts are the norm. You'll mostly likely get a roll with marmalade or jam, occasionally a slice of ham or cheese, and coffee or tea. The good news? These little breakfasts compel you to sample regional favorites: In Spain, look for chocolate con churros (fritters served with a thick, warm chocolate drink), pan con tomate (a toasted baguette rubbed with fresh garlic and ripe tomato), or a tortilla española (a hearty slice of potato omelet). Italian breakfasts are particularly tiny, but the delicious red orange juice you get is made from Sicilian blood oranges. And you can buy a delightful toasted sandwich from a corner bar anywhere, anytime in Italy to make up for the minuscule breakfast. In France, locals just grab a warm croissant and coffee on the way to work. Queue up with the French and consider the yummy options: croissants studded with raisins, packed with crushed almonds, or filled with chocolate or cream. If you expect breakfast to be too sparse, plan ahead to supplement it with a piece of fruit and a wrapped chunk of cheese from a local market. Being a juice man, I keep a liter box of OJ in my room for a morning eye-opener. Coffee drinkers know that breakfast is the only cheap time to caffeinate yourself. Some hotels will serve you a bottomless cup of a rich brew only with breakfast. After that, the cups acquire bottoms and refills will cost you. Juice is generally available at breakfast, but in Mediterranean countries, you have to ask…and you'll probably be charged. In many countries, breakfast is included in your hotel bill, though if you make prior arrangements with the hotelier, you may be able to skip breakfast and pay a lower price for the room. If breakfast costs extra, it's often optional, and you can usually save money and gain atmosphere by buying coffee and a roll or croissant at the café down the street or by brunching picnic-style in the park. When deciding whether to request breakfast, consider your timing; if you need to get an early start, skip the breakfast — few hotel breakfasts are worth waiting around for. Come to the European breakfast table with an adventurous spirit. I'm a big-breakfast traditionalist at home, but when I feel the urge for an American breakfast in Europe, I beat it to death with a hard roll. Can you make 5 questions based on the text

Create questions based on the following text Not long ago, I grabbed breakfast at a hotel in southern Spain. The only cereal available was a local version of frosted corn flakes, so I readied myself to enjoy a bowl of my childhood favorite. But my sweet indulgence wasn't what I'd expected: The cereal milk was heated — apparently standard in this part of Spain — and my poor frosted flakes immediately turned to mush. Not so grrrrrrreat. Soggy flakes or not, I find breakfast to be a fun part of my travel day, especially because the experience varies so much from one country's breakfast table to the next. The farther north you go in Europe, the heartier the breakfasts. The heaviest is the traditional British "fry." Also known as a "Plate of Cardiac Arrest," the fry is a fundamental part of the bed-and-breakfast experience, and is generally included in your room price. A standard fry comes with cereal or porridge, a fried egg, Canadian-style bacon or sausage (and sometimes mackerel or haggis), a grilled tomato, sautéed mushrooms, baked beans, and fried bread or toast. This protein-stuffed meal can tide me over until dinner. You'll quickly figure out which parts of the fry you like. Your host will likely ask you up front which breakfast items you actually like, rather than serve you the whole shebang and risk having to throw out uneaten food. The Scandinavian breakfasts buffet is the perennial favorite for the "most food on the table" award. It pays to take advantage of breakfast smorgasbords when you can. For about $20 (a cheap meal in these parts), you can dig into an all-you-can-eat extravaganza of fresh bread, cheeses, yogurt, cereal, boiled eggs, herring, cold cuts, and coffee or tea. In place of cereal and milk, Scandinavians like to pour thick yogurt over their granola. Throughout the Netherlands, Belgium, Germany, Austria, Switzerland, and most points east of there, expect a more modest buffet — but still plenty of options (rolls, bread, jam, cold cuts, cheeses, fruit, yogurt, and cereal). In these countries, there's a good chance of finding hard-boiled eggs, but scrambled or fried eggs are relatively rare. In Poland, track down jajecznica, the local wake-up call of eggs scrambled with kielbasa sausage, served with a side of potato pancakes. The breakfast of choice in Russia is oladi, pancakes perfectly fried to be crisp on the outside but soft in the middle, then topped with sour cream, honey, or berries. Germans have an endearing habit of greeting others in the breakfast room with a slow and dour "Morgen" ("Morning" — short for "good morning"), though they have plenty to be happy about. Breakfast is usually included, and offers hearty fuel for the day: ham, eggs, cheese, bread, rolls, and pots of coffee. In Switzerland, don't miss an opportunity to try Bircher Muesli, a healthful mix of oats, nuts, yogurt, and fruit that tastes far more delicious than it looks. If breakfast is optional, take a walk to the nearest bakery — every German, Austrian, and Swiss town has at least a few bakeries offering a world of enticing varieties of bread and pastries, baked fresh every morning. As you move south and west (France, Italy, Spain, and Portugal), skimpier "continental" breakfasts are the norm. You'll mostly likely get a roll with marmalade or jam, occasionally a slice of ham or cheese, and coffee or tea. The good news? These little breakfasts compel you to sample regional favorites: In Spain, look for chocolate con churros (fritters served with a thick, warm chocolate drink), pan con tomate (a toasted baguette rubbed with fresh garlic and ripe tomato), or a tortilla española (a hearty slice of potato omelet). Italian breakfasts are particularly tiny, but the delicious red orange juice you get is made from Sicilian blood oranges. And you can buy a delightful toasted sandwich from a corner bar anywhere, anytime in Italy to make up for the minuscule breakfast. In France, locals just grab a warm croissant and coffee on the way to work. Queue up with the French and consider the yummy options: croissants studded with raisins, packed with crushed almonds, or filled with chocolate or cream. If you expect breakfast to be too sparse, plan ahead to supplement it with a piece of fruit and a wrapped chunk of cheese from a local market. Being a juice man, I keep a liter box of OJ in my room for a morning eye-opener. Coffee drinkers know that breakfast is the only cheap time to caffeinate yourself. Some hotels will serve you a bottomless cup of a rich brew only with breakfast. After that, the cups acquire bottoms and refills will cost you. Juice is generally available at breakfast, but in Mediterranean countries, you have to ask…and you'll probably be charged. In many countries, breakfast is included in your hotel bill, though if you make prior arrangements with the hotelier, you may be able to skip breakfast and pay a lower price for the room. If breakfast costs extra, it's often optional, and you can usually save money and gain atmosphere by buying coffee and a roll or croissant at the café down the street or by brunching picnic-style in the park. When deciding whether to request breakfast, consider your timing; if you need to get an early start, skip the breakfast — few hotel breakfasts are worth waiting around for. Come to the European breakfast table with an adventurous spirit. I'm a big-breakfast traditionalist at home, but when I feel the urge for an American breakfast in Europe, I beat it to death with a hard roll.

FaB9_A Taste of Canada

Exploring the Culinary Revolution: A Taste of Molecular Gastronomy

5a a matter of taste

The Philippine Flag Our country is officially identified through our flag. The Philippine flag has three colors: white, blue, and red. White signifies purity; blue means hope and peace; and red denotes bravery. The three stars symbolize the three big groups of islands of our country-the Luzon, Visayas, and Mindanao. The eight rays of the sun signify the eight provinces that first revolted against the Spaniards. These are Bulacan, Pampanga, Tarlac, Nueva Ecija, Laguna, Batangas, Manila, and Cavite. We respect our flag to show that we respect our country. We should not treat it like an ordinary cloth because it symbolizes our country. An old flag should be burned and not be used as a rag. Title: National Hero Body text: Dr. Jose Rizal was from a middle-class family from Calamba, Laguna. He is regarded as a genius who fought the Spaniards through his writings, especially the novels "Noli Me Tangere" and "El Filibusterismo." The two novels exposed the anomalies and wrongdoings of the Spanish government against the Filipino people. He wrote the poem "Mi Ultimo Adios" the eve before his execution in Bagumbayan (now known as Rizal Park). National Fruit A mango is sour when it is green, but very sweet when it is ripe. This heart-shaped fruit symbolizes the kindness of the Filipinos. It has a big tree that bears fruits abundantly during summer. National Animal A carabao is a model of hard work and industry. It is the best companion of farmers in the field. It is black and looks like a tamaraw. A carabao is a very strong animal in terms of work. It symbolizes the Filipinos as hardworking and patient. National Bird The Philippine eagle, also known as haribon, stands over 5 feet (1.6 m) tall. It has a large, sharp, and aggressive beak and has powerful talons. Philippine eagles are excellent hunters, and live in tropical rainforests. These eagles lay just one or two eggs each year. National Tree The narra is a hardy tree that grows big and is found mainly in the Bicol Region, Mindanao, and Cagayan Valley forests. Most of the desks and tables in schools are made of narra. It signifies the strong personality of Filipinos in facing trials in life. National Flower The sampaguita has white, star-shaped petals with a sweet fragrance. It is made into garlands, which are given to visitors and special persons on occasions. It signifies purity and among Filipino women. National Fish Bangus or milkfish is our national fish. It grows in ponds or freshwater and tastes delicious. Its white, shiny scales signify our beautiful country. National Dance Cariñosa is a dance of love using a handkerchief and a fan. It symbolizes the true love expressed by Filipinos. National House A nipa hut is a small but beautiful house made from bamboo and sawali or cogon leaves. Filipinos used this kind of house during the olden times. At present, there are still people using this as a dwelling place, but most of the time, they use it as a rest place or cottage. National Costume Barong Tagalog is the national costume for Filipino men. It is made from pineapple fiber or other native materials. Filipinos wear this on special occasions such as formal events or weddings. Baro at Saya is the national dress for Filipino women. Most of them are made from jusi or pineapple fiber and other native materials. This dress shows the gracefulness of Filipino women. National Leaf Our national leaf is a palm tree. It is wide and narrow like an open fan. Farmers use this to protect their crops from the harsh sunlight and rain. It grows like a tree with thorns in its body. National Language Our national language is Filipino, which is based in Tagalog. Through the efforts of former President Manuel L. Quezon (known as the "Father of the National Language"), Filipino was widely disseminated and is now used in all parts of the country. With this, Filipinos in different cultures and native tongues can still communicate with each other. National Food Lechon (litson) is an important dish served at many occasions, especially on fiestas. Lechon is a suckling pig, slowly roasted over live coals to make it crispy and tasty. National Footwear Bakya is the national footwear of the Philippines. It was most popular from the 1950s to the 1970s before the introduction of rubber slippers. There are several colors and designs of bakya that suit the taste of most Filipinos. Valuing Our National Symbols Symbols represent a country and its people. We have to respect and value these symbols because they tell something about our country and of who we are as Filipinos. Here are some ways of valuing our national symbols: When singing the national anthem, stand straight and place your right hand on your left chest. Remove your cap or close your umbrella. Ask the people walking to stop while the flag is being raised. Tell other children to stop chatting while singing the national anthem. Most importantly, sing the national anthem wholeheartedly. Retirement of a Flag: A worn-out flag should be disposed of respectfully. It should be burned in a dignified ceremony, not thrown away or used for other purposes. Help in saving and conserving our forests. They serve as habitat of our national bird and other animals. You may also help organizations that promote reforestation, clean and green programs, and tree planting activities. Do not pick flowers when visiting parks. Instead, help in keeping these places clean and beautiful. Avoid throwing thrash in their surroundings. Patronize products that are made here in our country and made by Filipinos. Tell your family and friends to buy products of the Philippines especially those of which are our national symbol. Aside from patronizing our own products, let us use and love our national language. It is good to learn foreign languages, but do not forget to use our own language correctly and proudly.

A solution is a mixture in which one or more substances are uniformly distributed in another substance. Solutions can be mixtures of liquids, solids, or gases. For example, plasma, the liquid part of blood, is a very complex solution. It is composed of many types of ions and large molecules, as well as gases, that are dissolved in water. A solute (SAHL-YOOT) is a substance dissolved in the solvent. The particles that compose a solute may be ions, atoms, or molecules. The solvent is the substance in which the solute is dissolved. For example, when sugar, a solute, and water, a solvent, are mixed, a solution of sugar water results. Though the sugar dissolves in the water, neither the sugar molecules nor the water molecules are altered chemically. If the water is boiled away, the sugar molecules remain and are unchanged. Solutions can be composed of various proportions of a given solute in a given solvent. Thus, solutions can vary in concentra- tion. The concentration of a solution is the amount of solute dis- solved in a fixed amount of the solution. For example, a 2 percent saltwater solution contains 2 g of salt dissolved in enough water to make 100 mL of solution. The more solute dissolved, the greater is the concentration of the solution. A saturated solution is one in which no more solute can dissolve. Aqueous (AY-kwee-uhs) solutions—solutions in which water is the solvent—are universally important to living things. Marine microorganisms spend their lives immersed in the sea, an aqueous solution. Most nutrients that plants need are in aqueous solutions in moist soil. Body cells exist in an aqueous solution of intercellu- lar fluid and are themselves filled with fluid; in fact, most chemical reactions that occur in the body occur in aqueous solutions. Copyright © by Holt, Rinehart and Winston. All rights reserved. Liquid water Solid water Ice (solid water) is less dense than liquid water because of the structure of ice crystals. The water molecules in ice are bonded to each other in a way that creates large amounts of open space between the molecules, relative to liquid water. FIGURE 2-12 solvent from the Latin solvere, meaning “to loosen” Word Roots and Origins CHEMISTRY OF LIFE 43 ACIDS AND BASES One of the most important aspects of a living system is the degree of its acidity or alkalinity. What do we mean when we use the terms acid and base? Ionization of Water As water molecules move about, they bump into one another. Some of these collisions are strong enough to result in a chemical change: one water molecule loses a proton (a hydrogen nucleus), and the other gains this proton. This reaction really occurs in two steps. First, one molecule of water pulls apart another water molecule, or dissociates, into two ions of opposite charge: H2O ∏ H OH The OH ion is known as the hydroxide ion. The free H ion can react with another water molecule, as shown in the equation below. H H2O ∏ H3O The H3O ion is known as the hydronium ion. Acidity or alkalin- ity is a measure of the relative amounts of hydronium ions and hydroxide ions dissolved in a solution. If the number of hydronium ions in a solution equals the number of hydroxide ions, the solution is said to be neutral. Pure water contains equal numbers of hydro- nium ions and hydroxide ions and is therefore a neutral solution. Acids If the number of hydronium ions in a solution is greater than the number of hydroxide ions, the solution is an acid. For example, when hydrogen chloride gas, HCl, is dissolved in water, its mol- ecules dissociate to form hydrogen ions, H, and chloride ions, Cl, as is shown in the equation below. HCl ∏ H Cl These free hydrogen ions combine with water molecules to form hydronium ions, H3O. This aqueous solution contains many more hydronium ions than it does hydroxide ions, making it an acidic solution. Acids tend to have a sour taste; how- ever, never taste a substance to test it for acidity. In concentrated forms, they are highly corrosive to some materials, as you can see in Figure 2-13. Bases If sodium hydroxide, NaOH, a solid, is dissolved in water, it dissociates to form sodium ions, Na, and hydroxide ions, OH, as shown in the equation below. NaOH ∏ Na OH Copyright © by Holt, Rinehart and Winston. All rights reserved. Eco Connection onnection Acid Precipitation Acid precipitation, more commonly called acid rain, describes rain, snow, sleet, or fog that contains high levels of sulfuric and nitric acids. These acids form when sulfur dioxide gas, SO2, and nitrogen oxide gas, NO, react with water in the atmosphere to produce sulfuric acid, H2SO4, and nitric acid, HNO3. Acid precipitation makes soil and bodies of water, such as lakes, more acidic than normal. These high acid levels can harm plant and animal life directly. A high level of acid in a lake may kill mollusks, fish, and amphibians. Even in a lake that does not have a very elevated level of acid, acid precipitation may leach aluminum and magnesium from soils, poisoning water- dwelling species. Reducing fossil-fuel consump- tion, such as occurs in gasoline engines and coal-burning power plants, should reduce high acid levels in precipitation. Sulfur dioxide, SO2, which is produced when fossil fuels are burned, reacts with water in the atmosphere to produce acid precipitation. Acid precipitation, or acid rain, can make lakes and rivers too acidic to support life and can even corrode stone, such as the face of this statue. FIGURE 2-13 44 CHAPTER 2 This solution then contains more hydroxide ions than hydronium ions and is therefore defined as a base. The adjective alkaline refers to bases. Bases have a bitter taste; however, never taste a substance to test for alkalinity. They tend to feel slippery because the OH ions react with the oil on our skin to form a soap. In fact, commercial soap is the product of a reaction between a base and a fat. pH Scientists have developed a scale for comparing the relative con- centrations of hydronium ions and hydroxide ions in a solution. This scale is called the pH scale, and it ranges from 0 to 14, as shown in Figure 2-14. A solution with a pH of 0 is very acidic, a solution with a pH of 7 is neutral, and a solution with a pH of 14 is very basic. A solution’s pH is measured on a logarithmic scale. That is, the change of one pH unit reflects a 10-fold change in the acidity or alkalinity. For example, urine has 10 times the H3O ions at a pH of 6 than water does at a pH of 7. Vinegar, has 1,000 times more H3O ions at a pH of 3 than urine at a pH of 6, and 10,000 times more H3O ions than water at a pH of 7. The pH of a solution can be measured with litmus paper or with some other chemical indicator that changes color at various pH levels. Buffers The control of pH is important for living systems. Enzymes can function only within a very narrow pH range. The control of pH in organisms is often accomplished with buffers. Buffers are chemi- cal substances that neutralize small amounts of either an acid or a base added to a solution. As Figure 2-14 shows, the composition of your internal environment—in terms of acidity and alkalinity— varies greatly. Some of your body fluids, such as stomach acid and urine, are acidic. Others, such as intestinal fluid and blood, are

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