Question

Calcium metal reacts in an aqueous solution of nickel(III) sulphate to form calcium sulphate

solution and nickel metal. If 5.24 grams of nickel is produced, how many atoms of calcium
were used? (PLEASE HELP ME, I REALLY NEED HELP ASAP)

Answer 1

`8.065 * 10^(22)` atoms of Ca.

Step-by-step explanation:

Basic stoich question:

First the reaction is
`3Ca_((s)) +Ni_2(SO_4)_(3(aq)) --> 3CaSO_(4(aq)) + 2Ni_((s))`

Converting grams to moles:
`(5.24g)/(58.69g/mol) = 0.0892826 moles.`

Notice the mole ratio. For every 2 Ni produced, 3 Ca was used.

`0.08928267166 moles * (3)/(2) = 0.133924 moles` of Ca.

There are
`6.022*10^(23)` atoms in a mole.

Thus, multiplying them together =
`8.065 * 10^(22)` atoms