An atom of an element is 13 times heavier than the mass of a carbon atom. What is its mass in a.m.u. ?

Answer

To find the mass of the atom of the element in atomic mass units (a.m.u.), follow these steps:

### Step-by-Step Solution:

1. **Identify the mass of a carbon atom**:
The mass of a carbon atom is given as 12 a.m.u.

2. **Determine the relationship between the element and carbon**:
The problem states that the atom of the element is 13 times heavier than the mass of a carbon atom.

3. **Calculate the mass of the element**:
To find the mass of the element, multiply the mass of the carbon atom by 13:
\[ \text{Mass of the element} = 13 \times \text{mass of carbon atom} = 13 \times 12 \, \text{a.m.u.} \]

4. **Perform the multiplication**:
\[ 13 \times 12 = 156 \, \text{a.m.u.} \]

5. **State the final answer**:
Therefore, the mass of the atom of the element is 156 a.m.u.

### Final Answer:
The mass of the atom of the element is **156 a.m.u.**

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