Question

1. copper - find the mass of the copper wire.

a) calculate the number of moles in the sample.
b) calculate the number of copper atoms in the sample.

Explanation:

Step1: Calculate the number of moles

The formula for calculating the number of moles \(n\) is \(n=\frac{m}{M}\), where \(m\) is the mass and \(M\) is the molar mass. Given \(m = 0.34\space g\) and \(M=63.546\space g/mol\).

$$n=\frac{0.34}{63.546}$$

$$n\approx0.00535\space mol$$

Step2: Calculate the number of atoms

The number of atoms \(N\) is calculated using \(N = n\times N_{A}\), where \(N_{A}=6.022\times 10^{23}\space mol^{-1}\) (Avogadro's number). Substitute \(n = 0.00535\space mol\) into the formula.

$$N=0.00535\times6.022\times 10^{23}$$

$$N\approx3.22\times 10^{21}\space atoms$$

Answer:

a) The number of moles is approximately \(0.00535\space mol\).
b) The number of copper atoms is approximately \(3.22\times 10^{21}\space atoms\).