Unit 2 Quantities in Chemical Reactions

Question 1

Formula Mass

Answer 1

Mass of the molecule (Atomic Masses added together)

Question 2

Atomic Mass

Answer 2

Weight of an atom of a substance. Unit = amu, symbol = u

Question 3

Molar Mass

Answer 3

Same as Formula Mass. Unit = g/mol

Question 4

The Mole

Answer 4

Avogadro’s #. Symbol = n

Question 5

Entities

Answer 5

formula unit (fu)- ionic compound
molecules- molecular substance (HOFBrINCl)
atoms- anything not HOFBrINCl
ions- F- / NO3(1-)

Question 6

Avogadro’s #

Answer 6

(NA)= 6.02x10^23entities

Question 7

Percent Composition

Answer 7

Mass of Element/Total Mass of Substance

Question 8

Empirical Formula

Answer 8

Simplest whole number ratio of atoms

Question 9

Molecular Formula

Answer 9

Chemical formula

Question 10

Empirical vs. Molecular for Ionic Compounds

Answer 10

Same since f.u. contains simplest ratio of ions.