An apparatus used for the measurement of quantity of electricity is known as

Options

A. calorimeter
B. cathetometer
C. coulometer
D. colorimeter

Explanation

To solve the question "An apparatus used for the measurement of quantity of electricity is known as", let's break it down step by step.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for an apparatus specifically designed to measure the quantity of electricity. This refers to the amount of electric charge or current that passes through a conductor.

2. **Identifying Relevant Terms**:
- **Calorimeter**: This is used to measure heat and energy changes in chemical reactions, not electricity.
- **Cathetometer**: This instrument measures vertical distances, particularly in precise applications, but is not related to electricity.
- **Coulometer**: This device is used to measure the quantity of electricity, specifically in electrochemical processes, by measuring the amount of substance deposited or dissolved during electrolysis.
- **Colorimeter**: This instrument measures the concentration of colored solutions and is not used for measuring electricity.

3. **Selecting the Correct Answer**: Among the options analyzed, the only apparatus that measures the quantity of electricity is the **Coulometer**.

4. **Final Answer**: Therefore, the answer to the question is that an apparatus used for the measurement of quantity of electricity is known as a **Coulometer**.