In a zero order reaction, the rate
- A. doubles when the concentration doubles
- B. is independent of the concentration of the reactant
- C. falls to zero immediately
- D. is proportional to the square of the concentration
Explanation
A zero order reaction proceeds at a constant rate until the reactant is nearly exhausted, because something other than concentration limits it, typically a saturated catalyst surface or a fixed light intensity. The graph of concentration against time is therefore a straight line with a constant slope. Enzyme catalysed reactions become zero order once every active site is occupied.