Find moles of Cu atom and number of Cu atoms in it's 0.635 gm

Answer

To solve the problem of finding the moles of copper (Cu) atoms and the number of Cu atoms in 0.635 grams, we will follow these steps:

### Step 1: Find the Atomic Weight of Copper
The atomic weight of copper (Cu) is approximately 63.5 g/mol.

### Step 2: Calculate the Moles of Copper
To find the moles of copper, we use the formula:
\[ \text{Moles of Cu} = \frac{\text{Weight of Cu}}{\text{Atomic Weight of Cu}} \]
Given that the weight of copper is 0.635 grams, we can substitute the values:
\[ \text{Moles of Cu} = \frac{0.635 \, \text{g}}{63.5 \, \text{g/mol}} \]
Calculating this gives:
\[ \text{Moles of Cu} = 0.01 \, \text{mol} \]

### Step 3: Calculate the Number of Copper Atoms
To find the number of atoms, we use Avogadro's number, which is approximately \(6.02 \times 10^{23}\) atoms/mol. The formula to calculate the number of atoms is:
\[ \text{Number of Cu atoms} = \text{Moles of Cu} \times \text{Avogadro's Number} \]
Substituting the values we have:
\[ \text{Number of Cu atoms} = 0.01 \, \text{mol} \times 6.02 \times 10^{23} \, \text{atoms/mol} \]
Calculating this gives:
\[ \text{Number of Cu atoms} = 6.02 \times 10^{21} \, \text{atoms} \]

### Final Answers
- Moles of Cu: **0.01 mol**
- Number of Cu atoms: **\(6.02 \times 10^{21}\) atoms**

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