How much calcium is there in the amount of `Ca(NO_3)_2` that contains 20 g of nitrogen?

Explanation

To find out how much calcium is present in the amount of calcium nitrate (Ca(NO₃)₂) that contains 20 g of nitrogen, we can follow these steps:

### Step 1: Determine the molar mass of calcium nitrate (Ca(NO₃)₂)
The molar mass of calcium nitrate can be calculated as follows:
- Calcium (Ca): 40 g/mol
- Nitrogen (N): 14 g/mol (2 nitrogen atoms in the formula)
- Oxygen (O): 16 g/mol (6 oxygen atoms in the formula)

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