What are the number of moles of 0.4g of calcium?

1 Answer
Apr 25, 2018

#0.01mol_"Ca"#

Explanation:

Remember that to find moles of a substance, multiply the mass of said substance by its molar mass.

#.4g_"Ca"* (1 mol_"Ca")/(40.078g_"Ca")#

The grams cancel out, leaving #.4/40.078 = 0.01mol_"Ca"# (1 sig fig)