paper 2 questions

Question 1

why is thermometer adequate to determine the enthalpy change

Answer 1

temperature change is bigger than uncertainty

Question 2

carbon monoxide reacting with nitrogen monoxide in a catalytic converter

Answer 2

2CO + 2NO -> 2CO2 + N2

Question 3

suggest why anti-bumping granules prevent bumping?

Answer 3

from smaller bubbles

Question 4

give one reason why bonds in molecules such as CO2 and 1,1,1-trifluoroethane absorb infrared radiation

Answer 4

bonds vibrate

Question 5

Suggest why the student chose not to carry out experiments at temperature in the range of one to 10°

Answer 5

Reaction will take a long time

Question 6

What is stereoisomerism?

Answer 6

Molecules with the same structural formula but different arrangements of atoms in space

Question 7

Why is the plasticiser used in PVC?

Answer 7

Makes it more flexible

Question 8

Why is the plasticiser used in PVC?

Answer 8

Makes it more flexible

Question 9

What statement is correct about thermal cracking?
A. A pressure between 100 and 200 kPa is used.
B. Aromatic hydrocarbons on a major products.
C. C-C are broken.
D. Zeolite Catalysts are used.

Answer 9

C. C-C are broken.

Question 10

What statement is correct about the production and use of ethanol as a biofuel?
A. Biofuel ethanol is produced by the fermentation of glucose in a presence of yeast and air.
B. Ethanol is purified by fractional distillation.
C. Carbon dioxide is released when bioethanol was burned.
D. Bioethanol burns with a clean flame ethanol made by hydration of Ethane

Answer 10

B. Ethanol is purified by fractional distillation.

Question 11

Explain why PVC melt that a higher temperature of chloroethene

Answer 11

They have larger intermolecular forces
Longer molecule

Question 12

Which statement is correct for the distribution curve of molecular energies in a gas?
A. The curve is symmetrical about the maximum.
B. There are always some molecules of zero energy.
C. The position of a maximum of a curve is not dependent on the temperature.
D. The mean energy of a molecules is greater than the most probable energy of the molecules.

Answer 12

D. The mean energy of a molecules is greater than the most probable energy of the molecules.

Question 13

Explain in terms of collision theory, the effect of increasing a concentration of hydrogen peroxide and a rate of reaction

Answer 13

• More particles
• Frequency of successful collision

Question 14

Explain why nonane has a higher boiling point than 2,4-dimethyl heptane

Answer 14

• nonane molecules packed close together
• More branches so weaker Vander Vaal forces