Calculate the mass (in g) of 6.74x10^22 atoms of K.

1. Calculate the number of moles of \( K \):

\text{Number of moles} = \frac{6.74 \times 10^{22}}{6.022 \times 10^{23}} \approx 0.112 \text{ moles}

2. Multiply the number of moles by the molar mass of \( K \):

\text{Mass (g)} = 0.112 \text{ moles} \times 39.1 \text{ g/mol} \approx 4.38 \text{ g}

The mass of \( 6.74 \times 10^{22} \) atoms of \( K \) is approximately:

4.38 \text{ g}