Unit 8 Exam Review

Front

What is an empirical formula?

Back

The simplest whole-number ratio of atoms of each element in a compound.

Front

What is the empirical formula of C25H45?

Back

C5H9

Front

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

Back

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

Front

What is the percent by mass of fluorine in CaF2?

Back

49%.

Front

What is percent composition?

Back

The percent by mass of an element in a compound.

Front

What is the empirical formula of butanoic acid, CH3(CH2)2COOH?

Back

C2H4O.

Front

How do you find the empirical formula from percent composition?

Back

Convert percentages to grams, find moles of each element, divide by the smallest number of moles.

Front

What is the empirical formula for 40.05% S and 59.95% O?

Back

SO3.

Front

What is the molar mass of CaF2?

Back

78 g/mol.

Front

What is the formula to calculate percent composition?

Back

(mass of element / total mass of compound) x 100%.