To a sample of an element X (at. wt. 70) another element Y (at. wt. 120) is to be added as an impurity. The ratio of the atoms in the mixture is to be `1:10^(-7)` . How many grams of Y will be required for 35 g of X?

Explanation

To solve the problem, we need to determine how many grams of element Y are required when added as an impurity to 35 grams of element X, given the atomic weights and the ratio of atoms.

### Step-by-Step Solution:

1. **Identify the Given Data:**
- Atomic weight of element X (A_X) = 70 g/mol
- Atomic weight of element Y (A_Y) = 120 g/mol
- Mass of element X (m_X) = 35 g
...