Fill in the blanks by choosing the appropriate word/words from those given in the brackets :
(more than, primary, cathode, Lucas reagent, two, four, less than, Grignard's -reagent, tertiary, anode, zero, equal to, three)
When the concentration of a reactant of first order reaction is doubled, the rate of reaction becomes ________ times, but for a _________ order reaction, the rate of reaction remains the same.

Explanation

To solve the given question, we need to analyze the behavior of first-order and zero-order reactions in terms of how the rate of reaction changes with the concentration of the reactant.

### Step-by-Step Solution:

1. **Understand the Rate Law for First-Order Reactions**:
- For a first-order reaction, the rate law is given by:
\[
\text{Rate} = k[A]^1
...