Mole and % Comp Test

What is the molar mass of AuCl₃?

• 96 g
• 130 g
• 232.5 g
• 303.3 g

What is the definition for Avogadro's number?

• number of grams per one mole of a substance
• whole number ratio that is a multiple of a chemical formula
• simplest, whole number ratio of a chemical formula
• 6.02 x 10^23 particles per one mole of a substance

What is the mass in grams of 5.90 mol C₈H_18?

• .0512 g
• 19.4 g
• 673 g
• 389 g

You have 3.5 L of H₂ (g) at STP. How many moles of gas are there?

• 22.4 mol
• 22.4 L
• 0.16 mol
• 0.16 L

How many molecules are in 3.6 grams of NaCl?

• 0.06
• 1.0x10²¹
• 1.3x10²⁶
• 3.7x10²²

Calculate the number of nitrogen atoms in 20.9 grams of nitrogen. (N2)

• 1.49 atoms

• 0.746 atoms

• 0.37 atoms

• 1.74 atoms

How many moles of Os are in 6.02 x 10²³ atoms?

• 76 moles

• 1 mole

• 6.02 x 10²³ moles

• 100 moles

How do you solve the following problem: How many grams are there in 7.5 moles of H2SO4?

• Convert liters to moles then moles to grams

• Convert particles to moles then moles to grams

• Convert moles to grams

• Convert grams to moles

Match the following...

• multiplying my avagadro's constant

• You convert moles to liters by...

• dividing by the molar mass

• You convert moles to particles by...

• dividing by 22.4L

• You convert grams to moles by...

• multiplying by 22.4L

• You convert moles to grams by...

• multiplying by the molar mass

• You convert liters to moles by...

Reorder the following in the order of steps on calculating molar mass

• Use the periodic table to determine the mass of each element

• add all of the different amounts

• Count the # of atoms of each element

• Multiply the number of atoms of each element by their mass