A gold sample contains 90%` of gold and the rest copper. How many atoms of gold are present in one gram of this sample of gold?

Explanation

To find out how many atoms of gold are present in one gram of a gold sample that contains 90% gold and the rest copper, we can follow these steps:

### Step-by-Step Solution:

1. **Assume the Mass of the Sample**:
To simplify calculations, we can assume the total mass of the gold sample is 100 grams. This is a convenient choice because it makes percentage calculations straightforward.

- Mass of the sample = 100 grams
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