The Mole Test Practice (2nd part)

Find the Molar Mass of:
Ga₂(SO₃)₃

• 280 g/mol
• 400 g/mol
• 380 g/mol
• 480 g/mol

What is the mass of 2.50 mol of oxygen gas O₂?

• 40 g
• 80 g
• 16 g
• 32 g

Tags

NGSS.HS-PS1-7

Which expression below show the correct method of determining the percent composition of Sodium in Na₂CO₃?

• %Na = (22.99g/106g) x 100
• %Na = (22.99g/106) / 100
• %Na = (45.98g/106g) x 100
• %Na = (106/45.98g) x 100

How many moles are in 16.94g of water?

• 16.94 mol H₂O
• 0.9401 mol H₂O
• 305.3 mol H₂O
• 1.063 mol H₂O

Tags

NGSS.HS-PS1-7

What is the empirical formula of the following molecular formula:  C₃H₆

• C₃H₆
• CH₂
• C₂H₄
• CH₃

Find the percent composition of Cu₂S?

• %Cu= 67.987 %S= 32.013
• %Cu= 79.854   %S= 20.145
• %Cu= 35.946   %S= 64.054

A formula with the lowest whole # ratio of elements in a compound is called

• Molecular Formula
• Chemical Formula
• Empirical Formula 
• Distance Formula

How many grams are in 1.2 x 10²⁴ atoms of C?

• 29.34 grams

• 23.94 grams

• 6.02 grams

• 1.21 grams

Tags

NGSS.HS-PS1-7

Which of the following methods should be used in order to calculate the molar mass of magnesium hydroxide?

• Add the masses of two moles Mg to the mass of one mole OH

• Add the total protons and neutrons.

• Add the masses of one mole Mg to the mass of one mole OH

• Add the masses of one mole Mg to the masses of two moles of OH.

Tags

NGSS.HS-PS1-7

Na + Cl2 → NaCl Coefficient for Sodium

• 1
• 2
• 4
• 5

Tags

NGSS.HS-PS1-7