rate of reaction - effect of surface area on rate

Question 1

What will particles in solution only react with?

Answer 1

particles on surface of solid

Question 2

What happens to the particles not on the surface of the solid?

Answer 2

the particles in solution can not react with them

Question 3

increase surface area of solid =

Answer 3

more collisions per second so rate increases

Question 4

what do smaller sized blocks of solid reactants have?

Answer 4

greater surface area to volume ratio than large blocks which means more particles on surface so more collisions per second. increase rate of reaction.

Question 5

investigation for effect of surface area on rate of reaction

Answer 5

1. marble chips contain calcium carbonate which react with hydrochloric acid to produce carbon dioxide gas.
2. measure volume of carbon dioxide gas to determine rate of reaction becomes proportional
3. then change surface area of chips. can be difficult measuring using a cyclinder as bubbles are rapid so use glass syringe for a more accurate result
   you can also measure mass of carbon dioxide gas lost as carbon dioxide produced = mass decreases.
   4.cotton wool allows carbon dioxide gas to escape but prevents acid from splashing out and causing an anomalous result