Question

05 question (1 point) coast tutorial problem tennantite is an ore of copper with the formula cu12as4s13. 1st attempt how many moles of copper are present in a sample of tennantite with a mass of 2890 grams? moles cu

Explanation:

Step1: Calculate molar mass of tennantite

The molar mass of Cu is approximately 63.55 g/mol, As is approximately 74.92 g/mol, and S is approximately 32.07 g/mol.
The molar mass of \(Cu_{12}As_{4}S_{13}\) is \(12\times63.55 + 4\times74.92+13\times32.07\)
\[

$$\begin{align*} &12\times63.55+4\times74.92 + 13\times32.07\\ =&762.6+299.68+416.91\\ =&1479.19\text{ g/mol} \end{align*}$$

\]

Step2: Calculate moles of tennantite

Use the formula \(n=\frac{m}{M}\), where \(m = 2890\text{ g}\) and \(M = 1479.19\text{ g/mol}\)
\(n=\frac{2890}{1479.19}\approx1.953\text{ mol}\)

Step3: Calculate moles of copper

In one - mole of \(Cu_{12}As_{4}S_{13}\), there are 12 moles of Cu.
So moles of Cu in 1.953 mol of \(Cu_{12}As_{4}S_{13}\) is \(1.953\times12 = 23.436\text{ mol}\)

Answer:

23.44 (rounded to two decimal places)