The molecular mass of a compound is 75
(i) What is the mass of `6.022xx10^(20)` molecules , in gm
(ii) How many molecules are in its 2.5 mg

Explanation

To solve the given problem, we will break it down into two parts as specified in the question.

### Part (i): Finding the mass of `6.022 x 10^20` molecules

1. **Understanding Molecular Mass**: The molecular mass of the compound is given as 75 g/mol. This means that 1 mole (which contains `6.022 x 10^23` molecules) of this compound weighs 75 grams.

2. **Calculate the mass of `6.022 x 10^20` molecules**:
- First, we need to find out how many grams correspond to `6.022 x 10^20` molecules.
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