The mass of a copper calorimeter is `40 g` and its specific heat in (SI) units is `4.2 xx 10^2 J^(@) C^-1kg^-1 ` The thermal capacity is.

Options

A. `(a)4 J ^(@)C^-1`
B. `(b)18.6 J`
C. `(c)16.8 j//kg`
D. `(d)16.8 J^(@) C^-1`

Explanation

To find the thermal capacity of the copper calorimeter, we can follow these steps:

### Step 1: Understand the Formula
The thermal capacity (C) is calculated using the formula:
\[ C = m \times c \]
where:
- \( C \) is the thermal capacity,
- \( m \) is the mass of the substance,
- \( c \) is the specific heat capacity.

### Step 2: Convert Mass to Kilograms
Given that the mass of the copper calorimeter is \( 40 \, \text{g} \), we need to convert this into kilograms:
\[ m = \frac{40 \, \text{g}}{1000} = 0.04 \, \text{kg} \]

### Step 3: Identify Specific Heat Capacity
The specific heat capacity of copper is given as:
\[ c = 4.2 \times 10^2 \, \text{J} \, \text{°C}^{-1} \, \text{kg}^{-1} \]

### Step 4: Calculate Thermal Capacity
Now, substitute the values of mass and specific heat capacity into the formula:
\[ C = m \times c \]
\[ C = 0.04 \, \text{kg} \times 4.2 \times 10^2 \, \text{J} \, \text{°C}^{-1} \, \text{kg}^{-1} \]

### Step 5: Perform the Calculation
Calculating the above expression:
\[ C = 0.04 \times 420 \]
\[ C = 16.8 \, \text{J} \, \text{°C}^{-1} \]

### Final Answer
Thus, the thermal capacity of the copper calorimeter is:
\[ C = 16.8 \, \text{J} \, \text{°C}^{-1} \]