Practice for Mole Intro test

What is the molar mass of AuCl₃? Remember to look at a periodic table for the mass number of each element & use a calculator. (There is 1 gold and 3 chlorine- so (1 x 196. 97) + (3 x 35.45) = ?)

• 96 g

• 130 g

• 232.5 g

• 303.3 g

How many moles of sulfur atoms are there in 5.0 g of sulfur? (use the periodic table for the mass and a calculator- 1 mole of sulfur weighs 32.06 grams- if you have only 5 grams of sulfur how many moles is that?)

• 160 mol

• 8.3 x 10^-24 mol

• 0.16 mol

• 2.7 x 10^-22 mol

Determine the number of atoms in 2.50 moles of zinc.

(use the periodic table for the mass and a calculator- 1 mole of zinc has 6.02 x 10^23 atoms so if you have 2.50 moles you need to multiply 2.50 x 6.02 x 10^23)

• 1.51 x 10²⁴ atoms

• 4.15 x 10^-24 atoms

• 2.71 x 10^-22 atoms

• 163 atoms

How many grams of NaCl (molar mass = 58.45g) are present in 11.00 moles? (use the periodic table for the mass and a calculator- 1 mole of NaCl weiths 58.45 g, how much does 11.00 moles weigh?)

• 0.4500 g

• 156.6 g

• 331.0 g

• 642.9 g

What are the units for molar mass?

• grams
• amu
• grams/mole
• liters

Find the Molar Mass of: Ga₂(SO₃)₃

Remember multiply that last 3 to both S and O in the parenthesis. Use the periodic table for the mass of each element!

• 280 g/mol

• 400 g/mol

• 380 g/mol

• 480 g/mol

What is the molar mass of Hydrogen Peroxide (H₂O₂)?

Get your periodic table and look to see how much Hydrogen and Oxygen weigh!

• 48.10 g/mol

• 34.02 g/mol

• 36.54 g/mol

• 35.51 g/mol

How many moles are in 16.94 g of water?

Water is H₂O. H₂O weighs 18.015 grams (found it by using the periodic table). So 1 mole of H₂O weighs 18.015 grams and the problem is giving you 16.94 grams)

Do you have more than 1 mole or less than 1 mole?

• 16.94 mol H₂O

• 0.9401 mol H₂O

• 305.3 mol H₂O

• 1.063 mol H₂O

What is the definition of molar mass?

• 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

Molar mass is in units of ________.

• grams
• grams/mole
• mole
• moles/gram

Tags

NGSS.HS-PS1-7