The document contains worked solutions to multiple choice questions about gases, atomic structure, and physical periodicity. For the first question, the correct diagram showing the behavior of an ideal gas at constant temperature is a linear relationship between pressure (p) and volume (V) on the axes. For the second question, the identity of elements with increasing ionization energies that follows the trend across a period is option A. For the third question, the number of moles of gas molecules in a second sample is calculated using the ideal gas law. For the fifth question, Dalton's atomic theory idea that is known to be correct is that atoms of the same element are identical in mass.

1. Answers to Timed Assignment on Gases, Atomic Structure and Physical Periodicity Section A

2. 1. Which one of the following diagrams correctly describes the behaviour of a fixed mass of ideal gas? (T is constant.) A B C D pv p pv p pv p pv p

3. 1. Which one of the following diagrams correctly describes the behaviour of a fixed mass of ideal gas? (T is constant.) All four graphs have the same axes.

4. 1. Which one of the following diagrams correctly describes the behaviour of a fixed mass of ideal gas? (T is constant.) All four graphs have the same axes. y axis - pV x axis - p

5. 1. Which one of the following diagrams correctly describes the behaviour of a fixed mass of ideal gas? (T is constant.) All four graphs have the same axes. y axis - pV x axis - p p V = n R T y = m

6. 1. Which one of the following diagrams correctly describes the behaviour of a fixed mass of ideal gas? (T is constant.) All four graphs have the same axes. y axis - pV x axis - p p V = n R T y = m pV p

7. 1. Which one of the following diagrams correctly describes the behaviour of a fixed mass of ideal gas? (T is constant.) A B C D pv p pv p pv p pv p

8. 1. Which one of the following diagrams correctly describes the behaviour of a fixed mass of ideal gas? (T is constant.) A B C D The answer is C pv p pv p pv p pv p

9. 2. The use of the Data Booklet is relevant in this question. The graph shows the first ionisation energy of five elements in order of increasing proton number. Which option correctly represents the identity of Elements 1, 2, 3, 4 and 5? 1 2 3 4 5 A Ti V Cr Mn Fe B Al Si P S Cl C C N O F Ne D P S Cl Ar K 4 1 3 2 5 IE proton number

10. 2. The use of the Data Booklet is relevant in this question. The graph shows the first ionisation energy of five elements in order of increasing proton number. 4 1 3 2 5 IE generally increases across the period. IE proton number

11. 2. The use of the Data Booklet is relevant in this question. The graph shows the first ionisation energy of five elements in order of increasing proton number. 4 1 3 2 5 IE generally increases across the period. The trend is not followed only at certain points IE proton number

12. 2. The use of the Data Booklet is relevant in this question. The graph shows the first ionisation energy of five elements in order of increasing proton number. 4 1 3 2 5 IE generally increases across the period. The trend is not followed only at certain points Element 5 does not follow the trend and is a lot lower than the rest of the elements. IE proton number

13. 2. The use of the Data Booklet is relevant in this question. The graph shows the first ionisation energy of five elements in order of increasing proton number. 4 1 3 2 5 IE generally increases across the period. The trend is not followed only at certain points Element 5 does not follow the trend and is a lot lower than the rest of the elements. Element 5 is an element that belongs to a quantum level that is further away. IE proton number

14. 2. The use of the Data Booklet is relevant in this question. The graph shows the first ionisation energy of five elements in order of increasing proton number. Which option correctly represents the identity of Elements 1, 2, 3, 4 and 5? 1 2 3 4 5 A Ti V Cr Mn Fe B Al Si P S Cl C C N O F Ne D P S Cl Ar K 4 1 3 2 5 IE proton number

15. 2. The use of the Data Booklet is relevant in this question. The graph shows the first ionisation energy of five elements in order of increasing proton number. Which option correctly represents the identity of Elements 1, 2, 3, 4 and 5? 1 2 3 4 5 A Ti V Cr Mn Fe B Al Si P S Cl C C N O F Ne D P S Cl Ar K 4 1 3 2 5 IE proton number

16. 2. The use of the Data Booklet is relevant in this question. The graph shows the first ionisation energy of five elements in order of increasing proton number. Which option correctly represents the identity of Elements 1, 2, 3, 4 and 5? 1 2 3 4 5 A Ti V Cr Mn Fe B Al Si P S Cl C C N O F Ne D P S Cl Ar K 4 1 3 2 5 IE proton number

17. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? A B C D

18. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? p V = n R T

19. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k . Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? p V = n R T Concentration of gas??

20. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k . Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? p V = n R T Concentration of gas?? = concentration of gas

21. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? p V = n R T Concentration of gas?? = concentration of gas =

22. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k . Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? p V = n R T Concentration of gas?? = concentration of gas = = k =

23. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? p V = n R T Concentration of gas?? = concentration of gas = = k = R remains constant in both cases

24. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? R =

25. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? R = In the second scenario 30 V = n R (300)

26. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? R = In the second scenario 30 V = n R (300) =

27. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? R = In the second scenario 30 V = n R (300) = =

28. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? R = In the second scenario 30 V = n R (300) = = =

29. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? A B C D

30. 3. An ideal gas exerts a pressure of 60 Pa when its temperature is 400 K and the concentration of the gas is k. Another sample of the same gas exerts a pressure of 30 Pa when its temperature is 300 K. How many molecules are present in unit volume of this second sample? A B C D

35. 5. The following ideas were those underlying John Dalton’s atomic theory, published in 1803. Which idea is known to be correct? A Atoms are indivisible. B Atoms are very small. C Atoms of an element are identical. D Atoms of one element always differ in mass from those or another element.

36. 5. The following ideas were those underlying John Dalton’s atomic theory, published in 1803. Which idea is known to be correct? A Atoms are indivisible. B Atoms are very small. C Atoms of an element are identical. D Atoms of one element always differ in mass from those or another element.

37. 5. The following ideas were those underlying John Dalton’s atomic theory, published in 1803. Which idea is known to be correct? A Atoms are indivisible. B Atoms are very small. C Atoms of an element are identical. D Atoms of one element always differ in mass from those or another element.

38. 5. The following ideas were those underlying John Dalton’s atomic theory, published in 1803. Which idea is known to be correct? A Atoms are indivisible. B Atoms are very small. C Atoms of an element are identical. D Atoms of one element always differ in mass from those or another element.

39. 5. The following ideas were those underlying John Dalton’s atomic theory, published in 1803. Which idea is known to be correct? A Atoms are indivisible. B Atoms are very small. C Atoms of an element are identical. D Atoms of one element always differ in mass from those or another element.

40. 5. The following ideas were those underlying John Dalton’s atomic theory, published in 1803. Which idea is known to be correct? A Atoms are indivisible. B Atoms are very small. C Atoms of an element are identical. D Atoms of one element always differ in mass from those or another element. 40 Ar 40 Ca

41. 5. The following ideas were those underlying John Dalton’s atomic theory, published in 1803. Which idea is known to be correct? A Atoms are indivisible. B Atoms are very small. C Atoms of an element are identical. D Atoms of one element always differ in mass from those or another element.

42. 5. The following ideas were those underlying John Dalton’s atomic theory, published in 1803. Which idea is known to be correct? A Atoms are indivisible. B Atoms are very small. C Atoms of an element are identical. D Atoms of one element always differ in mass from those or another element.