An enzyme catalysed reaction is heated to a temperature of 65 °C.
Which of the following best explains the effect this temperature increase would have on the enzymes?
The enzyme and substrate molecules will gain kinetic energy and collide more frequently
The bonds in the enzyme will vibrate more and break, which will cause a permanent change in the shape of the active site
The bonds in the enzyme will vibrate more and break, causing a temporary change in the shape of the active site
The active site of the enzyme will permanently change shape due to the increased speed of collisions between the substrate molecule and the active site
Students investigated the effect of pH on catalase activity. Each experiment was repeated at a different pH value (pH = 2, 4, 7, 9, 11) and was set up as follows:
Five potato cubes of similar dimensions were used as a source of catalase
This was added to 50 cm3 of hydrogen peroxide
The volume of oxygen released from this reaction was collected in a measuring cylinder
This was used to calculate the initial rate of the reaction in dm3min-1
Which of the rows in the following table correctly identifies the variables in this experiment?