Chemical Reactions Quiz

What are the main products of a combustion reaction?

• Hydrogen gas and oxygen

• Sodium chloride and hydrogen gas

• Carbon dioxide and water

• Oxygen and water

If an element is diatomic it should have a subscript of___

• 1, always

• 2, only when it is an element

• it shouldn't have a subscript, it should have a coefficent

• 2, when bonded in a compound

Answer explanation

The correct choice is 2 because a diatomic element should have a subscript only when it is an element, not when bonded in a compound.

What is the charge of Iron in this compound. (Hint: think swap drop method):

Fe₃(PO₄)₂

• 3+

• 2+

• 1+

• 6+

Answer explanation

The charge of Iron in Fe3(PO4)2 is 2+ because the overall charge of the compound is 0, and each phosphate ion has a charge of 3-. By using the swap drop method, we determine that Iron must have a charge of 2+.

The symbol for a substance dissolved in solution is ______

• (s)

• (l)

• (aq)

• (g)

Answer explanation

The correct symbol for a substance dissolved in solution is (aq), which stands for aqueous solution.

Fill in the blank. (Copper has a charge of 2+)

Cu+ AgNO₃ → Ag + _____

• Cu(NO₃)₂

• CuNO₃

• CuAg

• Cu

Answer explanation

Choose Cu(NO3)2 because copper has a 2+ charge, so it forms Cu2+ in the compound

Predict the products of this synthesis reaction: H₂ + Cl₂ →

• HCl

• H₂Cl₂

• H₂Cl

• HCl₂

Answer explanation

The correct product of the synthesis reaction H2 + Cl2 is HCl, as hydrogen and chlorine combine to form hydrogen chloride.

What type of reaction is this?

2 C₆H₁₄ + 19 O₂ → 12 CO₂ + 14 H₂O

• Single Replacement

• Double Replacement

• Combustion

• Decomposition

Answer explanation

The given reaction is a combustion reaction because it involves a fuel (C6H14) reacting with oxygen to produce carbon dioxide and water, releasing energy in the form of heat and light.

Predict the products for the this Single Replacement reaction:

K + HCl →

• KCl + H₂

• KHCl

• KH + Cl₂

• HCl + K₂

Answer explanation

In a single replacement reaction, a more reactive element replaces a less reactive element in a compound. Here, potassium (K) is more reactive than hydrogen (H), so it will replace H in HCl to form KCl and release hydrogen gas (H2). Therefore, the correct products are KCl + H2.

Predict the products for the this Double Replacement reaction:

AgNO₃ + KCl →

• AgCl + KNO₃

• AgK + ClNO₃

• KAg + NO₃Cl

• AgCl + 3 KNO

Answer explanation

In a double replacement reaction, the positive ions of the two reactants switch places. Ag from AgNO3 combines with Cl from KCl to form AgCl, and K from KCl combines with NO3 from AgNO3 to form KNO3.

Complete the balanced equation for this Double Replacement reaction.

3 NaOH + Fe(NO₃)₃ →

• NaFe + OH(NO₃)₃

• NaNO₃ + Fe(OH)₃

• 3 NaNO₃ + Fe(OH)₃

• 3 NaFe + 3 (OH)NO₃

Answer explanation

The correct answer is 3 NaNO3 + Fe(OH)3 because in a double replacement reaction, the positive ions of the two reactants switch places to form new compounds.