4.1.2 - Effect Of Surface Area

Question 1

For solids, Why might increasing the SURFACE AREA INCREASE
the RATE!?

Answer 1

. More of the solid is exposed to the other particles

. So the collision frequency is higher

. So there are more successful collisions per unit time

Question 2

How do you increase the surface area of a solid !?

Answer 2

. Increasing surface area is usually accomplished by CUTTING or GRINDING up the solid

Question 3

What experiment demonstrates The effect of SURFACE AREA on RATE !?

Answer 3

. The Marble Chip Experiment:
- the effect of surface area on rate is usually demonstrated by reacting Calcium Carbonate (marble) chips with Hydrochloric acid

Question 4

Input variable of the marble chip experiment:

Answer 4

. The sizes of the Calcium Carbonate strips

Question 5

Output variable of the marble chip experiment:

Answer 5

. The volume of Carbon Dioxide

Question 6

Control variables of the marble chip experiment:

Answer 6

. Mass of Calcium Carbonate

. Volume and concentration of Hydrochloric acid

. Temperature

Question 7

How do you measure the VOLUME of Carbon Dioxide produced in the MARBLE CHIP experiment!?

Answer 7

. The volume of carbon dioxide gas is measured using a GAS SYRINGE or an INVERTED MEASURING CYLINDER in water

Question 8

Why might both the HIGHER SURFACE AREA Calcium Carbonate and the ORIGINAL surface area Calcium Carbonate have the SAME FINAL VOLUME !?

Answer 8

. Same final volume, because the total amount of reactants hasn’t changed, eventually the reaction produces the same amount of carbon dioxide

Question 9

Why may the HIGHER SURFACE AREA line be STEEPER at the start (when observing a vol by time graph) against the ORIGINAL, normal surface area line !?

Answer 9

. Steeper start, because RATE HAS INCREASED, so volume of carbon dioxide is increasing faster