C7 - Reaction Rates and Energy Changes

Question 1

Rate of reaction depends on…

Answer 1

Temperature
Concentration
Catalyst
Surface area for solids

Question 2

Ways to measure rate of reaction

Answer 2

Precipitation (spot dissapears)
Change in mass (usually gas given off)
Volume of gas given off

Question 3

Experiment for SA and rate of reaction

Answer 3

HCl and marble chips
Volume of CO2
repeat with different SAV rations of the chips

Question 4

Experiment for concentration and rate of reaction

Answer 4

Magnesium metal with dilute HCl

Measure mass as hydrogen is given off and add different concentrations

Question 5

Experiment for temperature and rate of reaction

Answer 5

Sodium thiosulfate and HCl produce a cloudy precipitate
clear solutions produce yellow
Repeat at different temperature and measure time taken

Question 6

Catalyst and rate of reaction experiment

Answer 6

Decomposition of hydrogen peroxide
2H2O2=2H20+O2
Add manganese(IV) oxide catalyst
gas syringe
different catalysts

Question 7

Exothermic reactions

Answer 7

Combustion
Neutralisation
Oxidation

Question 8

Endothermic reactions

Answer 8

Thermal decomposition

Question 9

Energy required to make or break bonds?

Answer 9

Break

Question 10

Energy released when making or breaking bonds?

Answer 10

Making

Question 11

Things that change the position of equilibrium

Answer 11

Temperature
Pressure (gasses)
Concentration

Question 12

Making ammonia equation

Answer 12

N2(g) + 3H2(g) = 2NH3(g)

Question 13

Where do reactants for the Haber process come from?

Answer 13

Nitrogen - air

Hydrogen - natural gas/crude oil

Question 14

Haber process conditions

Answer 14

200 atm
450 degrees
iron catalyst

Question 15

Optimum for Haber process

Answer 15

High pressure
Low temperature (but slow rate of reaction)