Why did Mendeleev swap the order of some elements?

to group them by their chemical properties

to group them with elements which look similar

to group them with elements which smell the same

to group them by their physical properties

Why did Mendeleev leave gaps in his Periodic Table?

leave room for elements that had not yet been discovered

leave room so that the periodic table isn't too packed

leave room for isotopes of the elements

Why do elements in a group have similar chemical properties?

have the same number of electrons in their outer shell

have the same number of electrons

have the same number of protons

Where are metals and non-metals located on the Periodic Table?

metals to the left, non-metals to the right

metals to the bottom, non-metals to the top

metals to the right, non-metals to the left

metals to the top, non-metals to the bottom

Why are the alkali metals named this?

they are metals that react with water to form an alkali

they are metals that react with water to form a solution that can neutralise alkalis

they react with oxygen to form metal oxides

What is the general equation for the reactions of alkali metals with oxygen?

metal + oxygen $\rightarrow$ metal oxide

metal + water $\rightarrow$ metal hydroxide

metal + chlorine $\rightarrow$ metal chloride

metal + water $\rightarrow$ metal hydroxide + hydrogen

How does the reactivity of the alkali metals change down the group?

the most reactive element is in the middle of the group

Which of these statements is NOT a reason why it is easier for alkali metals to lose their outer electron as you move down the group?

greater number of neutrons making the nucleus larger

weaker electrostatic forces of attraction on the outermost electron

more shells/electrons so more shielding between the nucleus and outer electron

they are larger atoms, so the outermost negative electron is further from the positive nucleus

How do the melting points of the halogens change down the group?

increase (higher melting point)

Which of these statements is NOT a reason why it is harder for the halogens to gain an electron as you move down the group?

they gain more neutral neutrons that cancel out the attraction of the positive protons

they are larger atoms, so the outermost shell is further from the positive nucleus

they gain more electron shells so there is more shielding between the nucleus and outer shell

they gain more electron shells so there are weaker electrostatic forces of attraction acting on the outermost electron

Why are the noble gases inert?

they have full outer shells so do not need to lose or gain electrons

they have seven electrons in their outer shell and need to gain an electron

they have 0 electrons in their outer shell

they have one electron in their last shell and need to lose 1 electron

How do the melting points of the noble gases change down the group?

increase (higher melting point)

decreases (lower melting point)

C4: The Periodic Table

At the Movies ELA.7.R.C4.2

The Class Trip ELA.7.R.C4.1

Midnight in the Cellar ELA.7.R.C4.1

Q.1. Which of the adaptive change is characterized by the presence of One type epithelial change into another type epithelium? Atrophy Hypertrophy Metaplasia Hyperplasia Q.2. If the myocardium is deprived of oxygen supply for 10 minutes, it will develop what type of morphological change? A. Hypertrophy B. Reversible cell injury C. Irreversible cell injury D. Hyperplasia Q.3. If in a cell, nucleus shows Pyknosis, Karyolysis, which of the followings Would apply correctly? Adaptation Reversible cell injury Irreversible cell injury Q.4 Which of the following organ has greater glycolytic capacity ? A. Spleen B. Heart (Myocardium ) C. Liver D. Brain Q.5. Free radicals are produced by all of the followings EXCEPT: A. Nitric oxide, produced by endothelial cells, macrophages B. Radiant energy C. Exogenous chemicals D. Lymphocytes Q.6. The most common cause of Hemochromatosis is: A. Excessive intake of iron B. Excessive use of blood transfusions C. Excessive Hemolysis of Red blood cells Q.7. Out of the followings, one is not characteristic of Acute inflammation: A. Vasodilation B. Fibrosis C. Permeability change D. Emigration of Leukocytes Q.8. Gap between endothelial cells is facilitated by following factors EXCEPT: A. Histamine B. Leukotriens C. Nitric oxide D. Substance P Q.9. For transmigration of leukocytes, which of the following molecules plays the part? A. P-Selectin B. Integrin C. L-Selectin D. VCAM Q.10. Which are the two considered as Opsonins ? A. IgM and C5a B. IgG and C3 C. IgA and C9 D. IgE and C4

The expression 2 + 4 1 + 2 is equal to (A) 0 (B) 1 (C) 2 (D) 4 (E) 5 2. The ones (units) digit of 542 is 2. When 542 is multiplied by 3, the ones (units) digit of the result is (A) 9 (B) 3 (C) 5 (D) 4 (E) 6 3. Some of the 1 × 1 squares in a 3 × 3 grid are shaded, as shown. What is the perimeter of the shaded region? (A) 10 (B) 14 (C) 8 (D) 18 (E) 20 4. If 3x + 4 = x + 2, the value of x is (A) 0 (B) −4 (C) −3 (D) −1 (E) −2 5. Which of the following is equal to 110% of 500? (A) 610 (B) 510 (C) 650 (D) 505 (E) 550 6. Eugene swam on Sunday, Monday and Tuesday. On Monday, he swam for 30 minutes. On Tuesday, he swam for 45 minutes. His average swim time over the three days was 34 minutes. For how many minutes did he swim on Sunday? (A) 20 (B) 25 (C) 27 (D) 32 (E) 37.5 7. For which of the following values of x is x 3 < x2 ? (A) x = 5 3 (B) x = 3 4 (C) x = 1 (D) x = 3 2 (E) x = 2112 years, Janice will be 8 times as old as she was 2 years ago. How old is Janice now? (A) 4 (B) 8 (C) 10 (D) 2 (E) 6 10. In the diagram, pentagon T P SRQ is constructed from equilateral 4 P T Q and square P QRS. The measure of ∠ST R is equal to (A) 10◦ (B) 15◦ (C) 20◦ (D) 30◦ (E) 45◦ Q P R S T Part B: Each correct answer is worth 6. 11. In the diagram, which of the following points is at a different distance from P than the rest of the points? (A) A (B) B (C) C (D) D (E) E y A x 2 2 4 4 6 8 6 8 B C D E P 12. If x = 2 and y = x 2 − 5 and z = y 2 − 5, then z equals (A) −6 (B) −8 (C) 4 (D) 76 (E) −4 13. In the diagram, P QR is a straight line segment. If x + y = 76, what is the value of x? (A) 28 (B) 30 (C) 35 (D) 36 (E) 38 x° x° x° y° y° P Q R 14. The line with equation y = 2x − 6 is reflected in the y-axis. What is the x-intercept of the resulting line? (A) −12 (B) 6 (C) −6 (D) −3 (E) 0 15. Amy bought and then sold 15n avocados, for some positive integer n. She made a profit of $100. (Her profit is the difference between the total amount that she earned by selling the avocados and the total amount that she spent in buying the avocados.) She paid $2 for every 3 avocados. She sold every 5 avocados for $4. What is the value of n? (A) 100 (B) 20 (C) 50 (D) 30 (E) 8 16. If 3x = 5, the value of 3x+2 is (A) 10 (B) 25 (C) 2187 (D) 14 (E) 45

Time-Telling Quiz: Half Past the Hour Name: ______________________ Date: ______________ What does "half past" specifically mean on an analog clock? A) 15 minutes have passed B) 30 minutes have passed C) 45 minutes have passed D) The hour has just begun When the minute hand points to 6, what position represents "half past"? A) The start of the hour B) Exactly halfway through the hour C) The end of the hour D) A quarter of the way through the hour If the hour hand is between 4 and 5, and the minute hand is on 6, what time is it? A) 4:15 B) 4:45 C) 4:30 D) 5:00 Which statement best describes how the hour hand moves? A) It moves quickly between numbers B) It moves slowly between numbers C) It stays in one place all the time D) It moves only at the top of each hour How many minutes are in a complete circle on a clock? A) 12 minutes B) 24 minutes C) 60 minutes D) 30 minutes When reading an analog clock for "half past", which hand should you look at first? A) The hour hand B) The second hand C) The minute hand D) The decorative hand What is the most important position of the minute hand when identifying "half past"? A) Pointing to 3 B) Pointing to 12 C) Pointing to 6 D) Pointing to 9 If a clock shows half past 7, how would this be written numerically? A) 7:15 B) 7:45 C) 7:30 D) 8:00 Which of the following is TRUE about clock hands? A) The shorter hand always shows minutes B) The longer hand always shows hours C) The longer hand shows minutes, the shorter hand shows hours D) Both hands move at exactly the same speed What is the primary challenge when learning to read "half past" times? A) Remembering the minute hand must be on 6 B) Counting all the numbers on the clock C) Understanding what an hour is D) Knowing the difference between AM and PM Answer Key: B B C B C C C C C A

1. What does the name Mlungisi mean? A. The Helper B. The Fixer C. The Brave One D. The Giver → B 2. What kind of person is Mlungisi? A. Rebellious and lazy B. Always fixing problems and helping others C. A mysterious, quiet boy D. A selfish older cousin → B 3. What does the name Velile mean? A. One Who Builds B. The Beloved One C. He Who Popped Out of Nowhere D. He Who Carries Others → C 4. How does Velile behave according to Trevor? A. He is very responsible and hardworking B. He often vanishes and suddenly reappears C. He is a caring father figure D. He is always around to help the family → B 5. Patricia’s name means: A. She Who Gives Back B. She Who Demands More C. The Fighter D. The Lost One → A 6. What did Patricia do as a child in Soweto? A. She went to school and stayed away from others B. She took care of abandoned children and fed them C. She ran away from home frequently D. She helped her father manage a shop → B 7. Where did Patricia find the money to buy food for the children? A. From her allowance B. From selling her toys C. From collecting bottles from shebeens D. From stealing it → C 8. What is a shebeen in this context? A. A school for orphans B. A place for young kids to play C. An informal bar where men would drink D. A shelter for street children → C 9. How old was Patricia when she started helping other children? A. 4 or 5 B. 6 or 7 C. 10 or 11 D. Teenager → B 10. Why did Trevor’s mother choose the name “Trevor”? A. It was the name of her favorite Bible character B. It was her father’s name C. It had no meaning, and she wanted him to be free D. It was a popular name in her family → C 11. What does it mean that Trevor's name had “no precedent” in South Africa? A. It was illegal to use B. It had no cultural or family history C. It came from ancient African myths D. It was a translation of a Zulu name → B 12. What is the deeper reason behind Patricia giving Trevor a name with no meaning? A. She didn’t like traditional names B. She didn’t know what the name meant C. She wanted him to escape fate and create his own identity D. She thought names were unimportant → C 13. According to Trevor, what kind of effect do traditional Xhosa names usually have? A. They are just for decoration B. They are often meaningless C. They tend to become self-fulfilling D. They reflect colonial history → C 14. What literary device is mainly used in the idea of names becoming destiny? A. Hyperbole B. Irony C. Symbolism D. Pun → C 15. Trevor’s mother wanted him to be: A. Bound to cultural tradition B. Free to be anyone he wanted C. A preacher D. Another fixer like Mlungisi → B ★ True or False Questions (判断题)（共10题） 16. Trevor’s cousin Mlungisi was known for always creating trouble. → False 17. Velile’s name and personality are both connected to sudden appearances and disappearances. → True 18. Patricia started caring for others when she was already an adult. → False 19. Shebeens were places where children gathered to play and eat. → False 20. Patricia used money she earned at a job to feed other children. → False （她用换瓶子的钱） 21. Trevor’s name has no Biblical or cultural background. → True 22. Patricia believed that names could shape a person’s life. → True 23. Trevor’s mother gave him a name with no meaning because she didn’t care about names. → False 24. Xhosa names often carry strong cultural or symbolic meanings. → True 25. Trevor’s mother gave him a name with no meaning so that he could be free from expectations. → True

7.2.1 Critical Angle 1. The critical angle is the angle of incidence at which the refracted ray: A. Bends toward the normal B. Bends away from the normal C. Travels along the boundary D. Is totally reflected Answer: C 7.2.2 Snell’s Law & Critical Angle 2. Which formula correctly represents the critical angle c when light travels from medium 1 to medium 2? A. n1cos⁡c=n2 B. n2sin⁡c=n1 C. n1sin⁡c=n2 D. n1sin⁡c=n2sin⁡90∘ Answer: D 7.2.3 Total Internal Reflection 3. Total internal reflection occurs only when: A. Light travels from air to glass B. Angle of incidence is less than the critical angle C. Light travels from a denser to a rarer medium D. Refractive index of the second medium is greater Answer: C 4. Which condition is not required for total internal reflection? A. Light must travel from a denser medium B. Angle of incidence must exceed the critical angle C. Refractive index of second medium must be lower D. Light must strike at 90° Answer: D 7.2.4 Ray Diagrams & Angle Calculations 5. A ray in water (n = 1.33) hits the surface at 40°. Critical angle = 48.8°. What happens? A. Refraction only B. Total internal reflection C. No refraction D. Light stops Answer: A 7.2.5 Snell’s Law in Glass Blocks & Prisms 6. A ray enters glass (n = 1.5) from air at 30°. Which statement is correct? A. It bends away from the normal B. It bends toward the normal C. It travels straight D. It undergoes total internal reflection Answer: B 7. In a prism, the deviation of light occurs mainly because: A. Light slows down in glass B. Light speeds up in glass C. Light reflects internally D. Light cannot pass through glass Answer: A 7.2.6 Mirages 8. A mirage appears on a hot road because: A. Light reflects off the sky B. Light refracts through layers of air with different densities C. Light undergoes dispersion D. Light travels in straight lines only Answer: B 7.2.7 Dispersion Through a Prism 9. Dispersion occurs because: A. All colors refract equally B. Different wavelengths refract differently C. The prism reflects light D. White light cannot be refracted Answer: B 7.2.8 Rainbow Formation 10. A rainbow is formed due to: A. Refraction only B. Total internal reflection only C. Dispersion only D. Refraction + TIR + dispersion Answer: D 7.2.9 Optical Fibers 11. Optical fibers work mainly due to: A. Refraction B. Diffraction C. Total internal reflection D. Dispersion Answer: C 12. Which is an advantage of optical fibers? A. High signal loss B. Immune to electromagnetic interference C. Very heavy D. Slow data transmission Answer: B

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