Unit 6 Flashcard Review Honors

Front

What is the molar mass of C8H18?

Back

The molar mass of C8H18 (octane) is approximately 114.22 g/mol.

Front

How do you calculate the mass of a substance from moles?

Back

Mass (g) = Moles × Molar Mass (g/mol).

Front

What is percent composition in chemistry?

Back

Percent composition is the percentage by mass of each element in a compound.

Front

How do you find the percent composition of fluorine in CaF2?

Back

Percent composition of fluorine = (mass of fluorine in formula / molar mass of CaF2) × 100.

Front

What is the volume of 1 mole of gas at STP?

Back

At STP (Standard Temperature and Pressure), 1 mole of gas occupies 22.4 L.

Front

What is the volume of 1.5 moles of gas at STP?

Back

Volume = 1.5 moles × 22.4 L/mole = 33.6 L.

Front

What is an empirical formula?

Back

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

Front

How do you determine the empirical formula from a molecular formula?

Back

Divide the subscripts in the molecular formula by their greatest common divisor.

Front

What is the empirical formula of C4H6?

Back

The empirical formula of C4H6 is C2H3.

Front

What is the relationship between moles and volume for gases at STP?

Back

At STP, 1 mole of gas occupies 22.4 L.