Common brass is a copper and zinc alloy containing 37.0% zinc by mass and having a density of 8.48 g/cm3. a fitting composed of common brass has a total volume of 122.5 cm3 .

how many atoms of copper does the fitting contain?

how many atoms of zinc does the fitting contain?

Answer :

The number of atoms of copper are

The number of atoms of zinc are

Explanation :

First we have to calculate the total mass of brass.

Formula used :

Total mass of brass = 1038.8 g

Now we have to calculate the mass of zinc and copper.

As we are given that, 37 % zinc by mass that means 37 g of zinc present in 100 g of mixture.

Mass of zinc = 37 g

Total mass of mixture (brass) = 100 g

Mass of copper = 100 - 37 = 63 g

Mass of zinc =

Mass of copper =

Now we have to calculate the moles of zinc and copper.

Molar mass of zinc = 65.38 g/mole

Molar mass of copper = 63.55 g/mole

Now we have to calculate the number of atoms of copper.

As, 1 mole of copper contains number of copper atoms

So, 5.879 moles of copper contains number of copper atoms

The number of atoms of copper are

Now we have to calculate the number of atoms of zinc.

As, 1 mole of zinc contains number of zinc atoms

So, 10.29 moles of zinc contains number of zinc atoms

The number of atoms of zinc are