Question

A modern-day nickel is 25% nickel and 75% copper. Every nickel weighs exactly five grams. Using this information, how many nickel coins do you need to have before you have a mole of nickel?

Answer 1

Answer:

• 47 coins

Explanation:

The atomic mass of nickel is 58.963g/mol. Thus, one mole of nickel weighs "exactly" 58.693g.

How much nickel does every coin contain?

        $25\%\text{ of }5g=0.25\times 5g=1.25g\text{ of nickel per coin}$

How many times 58.693g contains 1.25g?

         $\dfrac{58.693g}{1.25g/coin}=46.95\approx47coins$

That means that you need to have 47 coins of nickel to have one mole of nickel.