In another set-up, a student has prepared a 3.64 g sample of CuCNS. How many molecules of CuCNS exist in this sample? (Avogadro's constant \( =6.022 \times 10^{23} \mathrm{~mol}^{-1} \) )

To find out how many molecules of CuCNS are in a 3.64 g sample, we first need to calculate the molar mass of CuCNS. The molar mass is calculated as follows: Copper (Cu) = 63.55 g/mol, Carbon (C) = 12.01 g/mol, Nitrogen (N) = 14.01 g/mol, and Sulfur (S) = 32.07 g/mol. Adding these together gives us approximately 121.64 g/mol for CuCNS. Now, we can convert the mass of the sample to moles: \[ \text{Moles of CuCNS} = \frac{3.64 \text{ g}}{121.64 \text{ g/mol}} \approx 0.0299 \text{ mol} \] Using Avogadro's constant to find the number of molecules: \[ \text{Number of molecules} = 0.0299 \text{ mol} \times 6.022 \times 10^{23} \text{ mol}^{-1} \approx 1.80 \times 10^{22} \text{ molecules} \] So, this sample contains approximately \(1.80 \times 10^{22}\) molecules of CuCNS!