Question 1

What is the purpose of adding bromine in CCl4 during the test for unsaturation?

Accepted Answer

To react with unsaturated compounds

Answer

To dissolve the substances

Answer

To enhance the color of the substances

Answer

To increase the density of the substances

Question 2

Which substances were prepared for the test for unsaturation in the laboratory activity?

Accepted Answer

Olive oil, oleic acid, vegetable oil, coconut oil

Answer

Hydrochloric acid, sulfuric acid, nitric acid, acetic acid

Answer

Water, salt, sugar, vinegar

Answer

Ethanol, methanol, propanol, butanol

Question 3

Why is it important to prevent cross-contamination of samples during the test?

Accepted Answer

To obtain accurate results for each substance

Answer

To make the samples taste better

Answer

To reduce waste

Answer

To save time

Question 4

What is the purpose of recording the number of bromine drops consumed in each test?

Accepted Answer

To measure the degree of unsaturation in each substance

Answer

To determine the density of the substances

Answer

To calculate the volume of CCl4 used

Answer

To estimate the cost of the experiment

Question 5

Which substance is commonly used as a cooking oil and was likely to react with bromine in the test?

Accepted Answer

Vegetable oil

Answer

Salt

Answer

Sugar

Answer

Water

Question 6

What does it mean if a substance consumes a large number of bromine drops during the test?

Accepted Answer

The substance is highly saturated

Answer

The substance is not suitable for the test

Answer

The substance is a strong acid

Answer

The substance is a solid

Question 7

Which of the following substances would most likely show the least degree of unsaturation in the test?

Accepted Answer

Coconut oil

Answer

Vegetable oil

Answer

Oleic acid

Answer

Olive oil

Question 8

What type of information does recording the number of bromine drops consumed provide about a substance?

Accepted Answer

Its level of unsaturation

Answer

Its color

Answer

Its taste

Answer

Its density

Question 9

What is the purpose of step 1 in the soap preparation process?

Accepted Answer

To weigh coconut oil

Answer

To prepare a detergent solution

Answer

To test for saponification

Answer

To mix the soap ingredients

Question 10

What is the purpose of pouring the soap mixture into a mold in step 3?

Accepted Answer

To allow the soap to set

Answer

To create a detergent solution

Answer

To test the pH

Answer

To rinse the soap

Question 11

In soap preparation, what indicates that saponification is complete?

Accepted Answer

The mixture produces suds and no oily globules form

Answer

The mixture becomes clear

Answer

The mixture turns red

Answer

The mixture solidifies instantly

Question 12

In Part III, what is the purpose of preparing a solution of powdered detergent in step 1?

Accepted Answer

To compare properties of soap and detergent

Answer

To rinse out soap from the container

Answer

To weigh the detergent

Answer

To test the pH of the soap

Question 13

How does the purpose in soap preparation (weighing coconut oil) relate to the overall process?

Accepted Answer

Weighing coconut oil is a necessary step to ensure the right amount of oil for saponification.

Answer

Weighing coconut oil is done to test the pH.

Answer

Weighing coconut oil is necessary to prepare the detergent solution.

Answer

Weighing coconut oil is unrelated to the soap preparation process.

Question 14

Why is it important to stir continuously in one direction during the saponification process?

Accepted Answer

It promotes even mixing and reaction.

Answer

It helps dissolve the oil in water

Answer

It prevents the formation of suds

Answer

It speeds up the cooling process

Question 15

How does the result of the saponification test relate to the quality of the soap being produced?

Accepted Answer

A positive result (suds, no oily globules) indicates successful saponification and quality soap.

Answer

The test only measures the soap's color.

Answer

The test result has no relation to soap quality.

Answer

A negative result indicates high soap quality

Question 16

How does the pH test relate to the comparison of soap and detergent properties?

Accepted Answer

pH differences between soap and detergent impact their cleaning abilities.

Answer

pH testing helps to determine the weight of soap and detergent.

Answer

pH testing is unrelated to soap and detergent comparison.

Answer

pH testing indicates the color of soap and detergent.

Question 17

How does the rinsing of the soap container relate to the overall safety and disposal of laboratory materials?

Accepted Answer

Rinsing ensures safe handling and disposal of materials containing NaOH.

Answer

Rinsing is only done to clean the container.

Answer

Rinsing helps cool down the soap mixture.

Answer

Rinsing the container is unnecessary for safety.

Question 18

In soap preparation process, why is it important to rinse out the remaining soap from the container with 50 mL of distilled water?

Accepted Answer

To neutralize any remaining NaOH.

Answer

To dilute the soap mixture.

Answer

To remove any excess coconut oil

Answer

To prevent contamination of the detergent solution.

Question 19

What is the primary objective of testing the pH of the soap and detergent solutions?

Accepted Answer

To assess their cleaning abilities based on pH differences

Answer

To determine the weight of the soap and detergent

Answer

To evaluate their viscosity.

Answer

To compare the colors of soap and detergents.

Question 20

How does the result of the pH test relate to the cleaning effectiveness of soap and detergent?

Accepted Answer

pH can help determine the suitability of soap or detergent for specific cleaning tasks.

Answer

pH has no relation to cleaning effectiveness.

Answer

Lower pH typically suggests better cleaning for both soap and detergent.

Answer

Higher pH indicates better cleaning.

Question 21

In the procedure to test the protein nature of enzymes, what is added to 5 mL of the catalase extract?

Accepted Answer

3 M NaOH

Answer

Glucose solution

Answer

CuSO4 solution

Answer

5 mL of water

Question 22

What is the purpose of adding water to the grated potato in the procedure?

Accepted Answer

To extract the enzyme

Answer

To dilute the enzyme

Answer

To preserve the enzyme

Answer

To increase enzyme activity

Question 23

What is the purpose of straining the potato-water mixture through cheesecloth in the procedure?

Accepted Answer

To remove large debris

Answer

To add flavor to the filtrate

Answer

To increase enzyme concentration

Answer

To extract DNA from the potato

Question 24

If filtering through filter paper takes too long in the procedure, what alternative material can be used?

Accepted Answer

Cotton or gauzed

Answer

Tissue paper

Answer

Plastic wrap

Answer

Aluminum foil

Question 25

In the final step of the procedure, what is the purpose of mixing 5 mL of the filtrate with 5 mL of 6% H₂O₂ and inserting a glowing wooden splint?

Accepted Answer

To test for the presence of a gas

Answer

To generate heat

Answer

To create a chemical reaction

Answer

To observe the color change

Question 26

What is the purpose of mixing 1 mL of 0.05 N HCl with saliva in Test Tube 1 of the procedure?

Accepted Answer

To create an acidic environment

Answer

To neutralize the pH

Answer

To dilute the saliva

Answer

To test the effects of temperature

Question 27

Which substance is added to Test Tube 2 in the procedure to create a neutral pH environment?

Accepted Answer

Distilled water

Answer

0.05 N NaOH

Answer

0.05 N HCl

Answer

1% Starch solution

Question 28

What is the purpose of placing the test tubes in a water bath maintained at body temperature (37°C) in the procedure?

Accepted Answer

To test the effect of pH on enzyme activity

Answer

To sterilize the test tubes

Answer

To accelerate the reaction

Answer

To observe the color changed

Question 29

What is the indicator used to determine the completion of the reaction in the procedure for testing the effect of pH on enzyme activity?

Accepted Answer

0.001 N iodine solution

Answer

0.001 N glucose solution

Answer

0.001 N sodium hydroxide

Question 30

What would be the expected outcome if, instead of 0.05 N NaOH, a strong acid like 0.1 N HCl were added to Test Tube 3 in the lab activity?

Accepted Answer

Starch hydrolysis would cease completely.

Answer

Starch hydrolysis would be faster than with NaOH.

Answer

Starch hydrolysis would proceed at the same rate as with NaOH.

Answer

Starch hydrolysis would be slower than with NaOH.

Question 31

How would the results differ if the water bath temperature was lowered to 10°C instead of maintaining it at body temperature (37°C) during the experiment?

Accepted Answer

Starch hydrolysis would be slower.

Answer

Starch hydrolysis would be faster.

Answer

The reaction would stop entirely.

Answer

The effect on starch hydrolysis would be negligible.

Question 32

If the saliva used in the experiment was preheated to 70°C before being added to the test tubes, what impact would this have on starch hydrolysis?

Accepted Answer

Starch hydrolysis would be slower.

Answer

Starch hydrolysis would stop completely.

Answer

The temperature change would not affect starch hydrolysis.

Answer

Starch hydrolysis would be faster.

Question 33

What additional control could be included in the experimental design to ensure the observed changes are solely due to pH effects and not other factors?

Accepted Answer

Include a test tube with only 0.05 N NaOH and no saliva.

Answer

Conduct the experiment with different starch concentrations.

Answer

Repeat the experiment using different sources of saliva.

Answer

Perform the experiment in complete darkness.

Question 34

If the concentration of the enzyme is doubled while keeping the temperature and pH constant, how would this affect the time required for starch hydrolysis to be complete?

Accepted Answer

The time would decrease.

Answer

The time would become unpredictable.

Answer

The time would increase.

Answer

The time would remain the same.

Question 35

Which of the following best explain why the disappearance of the blue-black color in the iodine solution is considered a reliable indicator of complete starch hydrolysis

Accepted Answer

Iodine forms a complex with starch, causing the color change.

Answer

The blue-black color signifies the presence of glucose.

Answer

The blue-black color indicates the formation of new molecules.

Answer

The blue-black color is the natural color of iodine solution.

Question 36

Considering the influence of temperature, predict the effect of raising the water bath temperature from 37°C to 50°C on the rate of starch hydrolysis.

Accepted Answer

The rate would increase.

Answer

The rate would remain constant.

Answer

The rate would become unpredictable.

Answer

The rate would decrease.

Question 37

What does the disappearance of the blue-black color in the iodine solution indicate in the context of starch hydrolysis?

Accepted Answer

The completion of glucose formation.

Answer

The presence of iodine in the solution.

Answer

The initial stage of the enzymatic reaction.

Answer

The formation of starch molecules.

Question 38

What is the purpose of recording the time in the experiment?

Accepted Answer

To assess the rate of starch hydrolysis.

Answer

To measure the volume of the solutions.

Answer

To identify the pH of the test tubes.

Answer

To determine the color of the iodine solution.

Question 39

Why is it mentioned that the time for starch hydrolysis may vary depending on factors such as temperature and pH?

Accepted Answer

To highlight the complexity of enzymatic reactions.

Answer

To emphasize the importance of using iodine solution.

Answer

To confuse the experimenters.

Answer

To discourage conducting the experiment.

Question 40

What is the primary purpose of maintaining the water bath at body temperature during the experiment?

Accepted Answer

To accelerate the reaction.

Answer

To neutralize the pH of the solutions.

Answer

To create a comfortable environment for the experimenters.

Answer

To observe color changes.

Question 41

What is the reactant in the catalase-catalyzed reaction described by the equation as shown

Accepted Answer

Hydrogen peroxide (H₂O₂)

Answer

Water (H₂O)

Answer

Catalase

Answer

Oxygen (O₂)

Question 42

What is the role of catalase in the given reaction equation?

Accepted Answer

It accelerates the reaction.

Answer

It neutralizes the products.

Answer

It is a product of the reaction.

Answer

It is a reactant in the reaction.

Question 43

How many molecules of oxygen (O₂) are produced in the catalase-catalyzed reaction when 2 molecules of hydrogen peroxide (H₂O₂) react?

Accepted Answer

2

Answer

1

Answer

4

Answer

3

Question 44

What are the products formed as a result of the catalase-catalyzed reaction?

Accepted Answer

Water (H₂O) and oxygen (O₂)

Answer

Water (H₂O) only

Answer

Oxygen (O₂) only

Answer

Water (H₂O) and catalase

Question 45

What is the primary function of catalase in the context of the hydrogen peroxide decomposition reaction?

Accepted Answer

To increase the rate of the reaction.

Answer

To increase the activation energy.

Answer

To inhibit the formation of products.

Answer

To decrease the rate of the reaction.

Question 46

Why is catalase considered a biological catalyst in the given context?

Accepted Answer

It accelerates reactions by lowering activation energy.

Answer

It increases the concentration of substrates.

Answer

It inhibits reactions.

Answer

It stabilizes the transition state.

Question 47

What is the optimal pH range for most enzymes to function efficiently?

Accepted Answer

Near-Neutral

Answer

Alkaline

Answer

Low acidity

Answer

High acidity

Question 48

In the context of enzyme activity, what term is used for molecules that enhance the enzyme's activity?

Accepted Answer

Activators

Answer

Inhibitors

Answer

Co-factors

Answer

Substrates

Question 49

What is the impact of increasing enzyme concentration on the rate of enzymatic reaction?

Accepted Answer

Increases rate

Answer

Stabilizes rate

Answer

Decreases rate

Answer

No impact

Question 50

Which molecules can reduce enzyme activity by binding to the enzyme?

Accepted Answer

Inhibitors

Answer

Substrates

Answer

Co-factors

Answer

Activators

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