Yeast is mixed with sugar solution at different temperatures. The volume of carbon dioxide produced in 10 minutes is measured.

Temperature in $∘C^\circ\mathrm{C}$	Volume of carbon dioxide in $cm3\mathrm{cm^{3}}$
20	12
30	25
37	34
45	18
60	0

The mixture at $∘C60\,^\circ\mathrm{C}$ is then cooled to $∘C37\,^\circ\mathrm{C}$ . It still produces no gas.

Statement 1: the results show that raising the temperature always increases the rate of an enzyme-catalysed reaction

Statement 2: enzymes are catalysts, so the enzymes in the yeast must still work normally after being heated to $∘C60\,^\circ\mathrm{C}$

Statement 3: above about $∘C37\,^\circ\mathrm{C}$ the rate falls even though the particles collide more often, so another factor must be involved

Statement 4: the result after cooling suggests that the enzymes were permanently changed at $∘C60\,^\circ\mathrm{C}$

Which statements are correct?

Yeast is mixed with sugar solution at different temperatures. The volume of carbon dioxide produced in 10 minutes is measured.

Temperature in $∘C^\circ\mathrm{C}$	Volume of carbon dioxide in $cm3\mathrm{cm^{3}}$
20	12
30	25
37	34
45	18
60	0

The mixture at $∘C60\,^\circ\mathrm{C}$ is then cooled to $∘C37\,^\circ\mathrm{C}$ . It still produces no gas.

Statement 1: the results show that raising the temperature always increases the rate of an enzyme-catalysed reaction

Statement 2: enzymes are catalysts, so the enzymes in the yeast must still work normally after being heated to $∘C60\,^\circ\mathrm{C}$

Statement 3: above about $∘C37\,^\circ\mathrm{C}$ the rate falls even though the particles collide more often, so another factor must be involved

Statement 4: the result after cooling suggests that the enzymes were permanently changed at $∘C60\,^\circ\mathrm{C}$

Which statements are correct?

8.1 Rates of reaction

8.1 Rates of reaction Questions