Reactions And Gas Laws

Question 1

What are the forms of matter?

Answer 1

elements - basic
compounds - 2 or more elements
mixtures - more than 1 substance eg air

Question 2

Physical changes?

Answer 2

Freezing of water
dissolving sugar in tea
dissolving oxygen in water
evaporation of water

Question 3

Chemical changes?

Answer 3

Burning of paper
Rusting of iron
Dissolving ammonia in water

Question 4

Chemical reactions?

Answer 4

Involve conversion of one type of matter into another to create a new substance with no change in total mass.

Question 5

Charcoal burning?

Answer 5

C + O2 = CO2

Question 6

Acid + base

Answer 6

Salt + water

Question 7

Acid + metal

Answer 7

Salt + H2

Question 8

How is ammonia formed?

Answer 8

By the haber process
N2 + 3H2 = 2NH3
400-450 degrees / 200atm / iron catalyst
High P, Low temp

Question 9

What does kinetic theory explain?

Answer 9

Density is lower in gases due to spaces between molecules

pressure results from particles hitting the side of the vessel

Question 10

What is the gas law?

Answer 10

PV = nRT

Question 11

What are the assumptions for the gas law?

Answer 11

gas particles are tiny and move in random directions
gas particles don’t attract one another
particle collisions don’t alter overall energy
particle volumes are negligible
R = 8.3145 Jmol^-1K^-1

Question 12

What is Boyle’s Law?

Answer 12

V is proportional to 1/P

volume is inversely proportional to pressure

Question 13

What is Charles’ Law?

Answer 13

V is proportional to T

0K = -273 degrees

Question 14

What is Avogadro’s Law?

Answer 14

V is proportional to n (number of moles)
1 mole = 6.022 x 10^23 molecules
equal volumes of all gases at the same pressure and temperature have the same number of molecules

Question 15

What is the volume of 1 mole at 293K, and 1 atm?

Answer 15

24 dm^3

Question 16

What is Dalton’s Law?

Answer 16

Total P = sum of partial pressures

Question 17

What is the partial pressure?

Answer 17

The pressure the gas would exert if it was in the container on its own.

Question 18

Oxygen in the air is in equilibrium with?

Answer 18

The oxygen in water

Question 19

When does the solubility of a gas increase?

Answer 19

With its partial pressure

Question 20

What happens if a gas is reactive?

Answer 20

It only works at low partial pressures.
C = Kh x pp
Concentration = Henry’s law constant x partial pressure

Question 21

What is Henry’s Law?

Answer 21

The equilibrium concentration at a known temperature is proportional to the partial pressure of the dissolving gas.
Kh varies for each gas

Question 22

What is the solubility of ammonia?

Answer 22

Highly soluble