Moles review

What is the molar mass of CaCO₃?

• 98 g/mol

• 100 g/mol

• 124 g/mol

• 130 g/mol

How many particles would be in 8.4 moles of Octane (C₈H₁₈)?

• 5.77 x 10²³
• 5.04 x 10²⁴
• 5.77 x 10²⁶
• 5.04 x 10²³

Tags

NGSS.MS-PS1-1

What is the percent by mass of magnesium in MgO?

• 20%
• 40%
• 50%
• 60%

A compound is 25.9 % nitrogen and 74.1% oxygen. Find its empirical formula. 

• N₂O₄
• NO
• N₂O₅
• N₄O₆

Epinephrine (adrenaline) is a hormone secreted into the bloodstream in times of stress. It contains 59.0% C, 7.15% H, 26.20%O, 7.65%N and has a molar mass of 183 g/mol. What is its molecular formula?

• C₉H₁₃NO₃

• C₅H₁₁N₃O₂

• C₈H₁₂NO₂

• C₇H₉N₂O

O₂ + CS₂ --> CO₂ + SO₂
What coefficient would go in front of the O₂?

• 1
• 2
• 3
• 4

Tags

NGSS.HS-PS1-7

What is a Excess Reagent?

• amount you end with
• what you run out of first
• what you have left over
• what you start with

Tags

NGSS.HS-PS1-7

What is a Limiting Reagent?

• speeds up a reaction
• what you run out of first
• what you have left over
• slows down a reaction

Tags

NGSS.HS-PS1-7

2H₂   +   O₂  →  2H₂O
How many moles of water can be produced if 8 moles H₂ are used?

• 4 moles
• 8 moles
• 16 moles
• 2 moles

Tags

NGSS.HS-PS1-7

Cl₂ + 2KBr → Br₂ + 2KCl
How many grams of potassium chloride (KCl) can be produced from 356 g of potassium bromide (KBr)?

• 749 g
• 223 g
• 479 g
• 814 g

Tags

NGSS.HS-PS1-7