Predicting products and balancing equation

When the equation Fe₃O₄ + Al --> Al₂O₃ + Fe is correctly balanced, what is the coefficient of Fe?

• 2
• 7
• 9
• 4

Tags

NGSS.HS-PS1-7

Given the balanced equations representing two chemical reactions:
1.    I₂ + 2 KBr --> 2ICl + Br₂
2.     2NaCl --> 2 Na + Cl₂
Which types of chemical reactions are represented by these equations?

• single replacement and double replacement
• synthesis and double replacement
• synthesis and decomposition
• single replacement and decomposition

Solid NaCl is produced by the reaction of metallic sodium with chlorine gas. This reaction is also accompanied by the release of heat energy. Which equation shows this reaction?

• 2Na (s) +  Cl₂ (g) -->2NaCl (s) + heat
• Na⁺  (aq) +  Cl^– (aq) --> NaCl (s) + heat
• 2NaCl (s) --> 2Na (s) +  Cl₂ (g)  +  heat
• NaCl (s) + heat  --> Na⁺  (aq) +  Cl^– (aq)

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-4

Which coefficients correctly balance the equation Fe(OH)₃ --> Fe₂O₃ + H₂O ?

• 2, 2, 2
• 2, 1, 3
• 3, 4, 1
• 1, 1, 1

Tags

NGSS.HS-PS1-7

In the chemical reaction,
2H₂ + O₂ --> 2H₂O, the reactant(s) is or are:

• H₂
• H₂O
• O₂
• H₂ and O₂

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-1

When the equation Fe₃O₄ + Al --> Al₂O₃ + Fe is correctly balanced, what is the coefficient of Fe?

• 2
• 7
• 9
• 4

Tags

NGSS.HS-PS1-7

BaF₂ + K3PO₄ --> Ba₃(PO₄)₂ + KF
What coefficient goes in front of K₃PO₄?

• 1
• 2
• 3
• 4

Tags

NGSS.HS-PS1-7

Determine the type of reaction:HgO --> Hg + O₂

• Synthesis
• Decomposition
• Single
• Combustion

Determine the type of reaction:Mg + HCl --> MgCl₂ + H₂

• Single Displacement
• Double
• Combustion
• Synthesis

Determine the type of reaction:Zn + H₂SO₄ --> ZnSO₄ + H₂

• Combustion
• Single Displacement
• Double
• Decomposition