Question

the chemical formula for magnesium sulfide is mgs. a chemist determined by measurements that 0.010 moles of magnesium sulfide participate in a chemical reaction. calculate the mass of magnesium sulfide that participates. be sure your answer has the correct number of significant digits.

Explanation:

Step1: Find molar - mass of MgS

The molar mass of Mg (magnesium) is approximately $24.31\ g/mol$, and the molar mass of S (sulfur) is approximately $32.07\ g/mol$. The molar mass of MgS, $M$, is the sum of the molar - masses of its elements. So $M = 24.31\ g/mol+32.07\ g/mol=56.38\ g/mol$.

Step2: Calculate the mass of MgS

We know that the number of moles, $n = 0.010\ mol$, and the mass, $m$, can be calculated using the formula $m=n\times M$. Substitute $n = 0.010\ mol$ and $M = 56.38\ g/mol$ into the formula: $m=0.010\ mol\times56.38\ g/mol = 0.5638\ g$. Rounding to 2 significant digits (since 0.010 has 2 significant digits), we get $m = 0.56\ g$.

Answer:

$0.56\ g$