Front

What is an empirical formula?

Back

An empirical formula is the simplest whole-number ratio of atoms of each element in a compound.

Front

What is the empirical formula for C4H10?

Back

C2H5

Front

How do you calculate percent by mass of an element in a compound?

Back

Percent by mass = (mass of element in 1 mole of compound / molar mass of compound) x 100%.

Front

What is the percent by mass of chlorine in NaCl?

Back

61%.

Front

What is the percent by mass of calcium in CaF2 (molar mass = 78 g/mol)?

Back

51%.

Front

What is the percent by mass of oxygen in MgO?

Back

40%.

Front

Which of the following is an empirical formula: N2O, Na2SO4, N2O4, Al3(SO4)2?

Back

N2O.

Front

What is the molar mass of NaCl?

Back

58.44 g/mol.

Front

What is the molar mass of CaF2?

Back

78 g/mol.

Front

What is the molar mass of MgO?

Back

40.31 g/mol.