Unit 4 Chemistry

2 KClO₃ → 2 KCl + 3 O₂
How many moles of oxygen are produced when 6.7 moles of KClO₃ decompose completely?

• 6.7 mol
• 1.0 mol
• 10.1 mol
• 4.5 mol

Tags

NGSS.HS-PS1-7

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

• 749 g
• 223 g
• 479 g
• 814 g

Tags

NGSS.HS-PS1-7

B₂H₆ + 3O₂ -->2 HBO₂ + 2 H₂O

What mass of O₂ will be needed to burn 36.1 g of B₂H₆?

• 13.8 g

• 3.86 g

• 124 g

• 198.3 g

What is the percent yield of the following reaction if 145g of P₂O₅ reacts with 40 grams of water, but you only collect 112 grams of phosphoric acid?

3 H₂O + P₂O₅ -> 2H₃PO₄

• 80%

• 85%

• 77%

• 58%

Tags

NGSS.HS-PS1-7

Balance the reaction: _AlBr₃ + _K₂SO₄ → _KBr + _Al₂(SO₄)₃

• 6 AlBr₃ + 1 K₂SO₄ → 6 KBr + 1 Al₂(SO₄)₃

• 2 AlBr₃ + 3 K₂SO₄ → 6 KBr + 1 Al₂(SO₄)₃

• 1 AlBr₃ + 1 K₂SO₄ → 2 KBr + 3 Al₂(SO₄)₃

• 2 AlBr₃ + 3 K₂SO₄ → 1 KBr + 2 Al₂(SO₄)₃

Tags

NGSS.HS-PS1-7

Fe + S --> FeS
If 7.62g Fe react with 8.67g S, what is the limiting reactant?

• Fe
• S
• FeS
• none 

Tags

NGSS.HS-PS1-7

What is the limiting reactant if 10 moles of NH₃ react with 30.0 moles of NO?

4NH₃+ 6NO --> 5N₂ + 6H₂O

• NH₃

• NO

• N₂

• water

Tags

NGSS.HS-PS1-7

What precipitate forms when you mix lead (II) nitrate with sodium chloride?

• sodium nitrate 
• lead (II) chloride 
• sodium lead
• chloride nitrate 

Which is the correct net ionic equation for the reaction of AgNO₃ and CaCl₂?

• Ca²⁺(aq) +  2Cl^- (aq) → CaCl(s)
• Ag⁺(aq)  +  Cl^- (aq) → AgCl(s)
• Ag +  Cl  →  AgCl
• Ag⁺  +  Ca²⁺   →Ag₂Ca (s)

Tags

NGSS.HS-PS1-7

Which of the following does NOT form a precipitate?

• Pb(NO₃)₂(aq) + 2KI(aq) →
• Sr(NO₃)_{2 (aq)} + K₂SO_4(aq) →
• AgNO₃(aq) + Na₂S(aq) →
•  Pb(NO₃)₂(aq) + AgNO₃(aq) →