Calculate the mass of 5 moles of `CaCO_3` in grams.

Answer

To calculate the mass of 5 moles of calcium carbonate (CaCO₃), we need to follow these steps:

### Step 1: Determine the molar mass of CaCO₃
To find the molar mass, we need to add the atomic masses of each element in the compound.

- Calcium (Ca): 40 g/mol
- Carbon (C): 12 g/mol
- Oxygen (O): 16 g/mol (and there are 3 oxygen atoms in CaCO₃)

Now, calculate the total molar mass:
\[ \text{Molar mass of CaCO}_3 = \text{mass of Ca} + \text{mass of C} + 3 \times \text{mass of O} \]
\[ = 40 + 12 + (3 \times 16) \]
\[ = 40 + 12 + 48 \]
\[ = 100 \text{ g/mol} \]

### Step 2: Use the formula to find the mass
The relationship between moles, mass, and molar mass is given by the formula:
\[ \text{Number of moles} = \frac{\text{Mass (grams)}}{\text{Molar mass (g/mol)}} \]
Rearranging this formula to find the mass gives us:
\[ \text{Mass} = \text{Number of moles} \times \text{Molar mass} \]

### Step 3: Substitute the values
We know that we have 5 moles of CaCO₃ and the molar mass is 100 g/mol:
\[ \text{Mass} = 5 \text{ moles} \times 100 \text{ g/mol} \]
\[ = 500 \text{ grams} \]

### Final Answer
The mass of 5 moles of CaCO₃ is **500 grams**.

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