Chemistry Honors Review - Understanding Moles and Formulas

What is the definition of a mole in chemistry?

• The mass of one atom of an element

• The volume of one liter of gas

• The number of protons in an atom

Which of the following is the correct formula to calculate molar mass?

• Add the atomic masses of all atoms in a molecule

• Divide the atomic number by the number of atoms

• Multiply the atomic mass by Avogadro’s number

• Subtract the number of neutrons from the atomic mass

What is the empirical formula?

• The formula showing the actual number of atoms in a molecule

• The simplest whole-number ratio of atoms in a compound

• The formula showing the arrangement of atoms

• The formula with the highest possible subscripts

Which of the following best describes percent composition?

• The ratio of atoms in a molecule

• The percentage by mass of each element in a compound

• The number of moles in a sample

• The total mass of a compound

What is dimensional analysis used for in chemistry?

• To determine the color of a compound

• To convert units and solve problems using conversion factors

• To measure temperature

• To find the boiling point

• 10 g/mol

• 16 g/mol

• 18 g/mol

• 20 g/mol

• 1 mole

• 2 moles

• 3 moles

• 0.5 moles

Tags

NGSS.HS-PS1-7

A compound contains 40% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. What is its empirical formula?

• 11.1%

• 33.3%

• 66.7%

• 88.9%