FLVS Chemistry: Module 4 Notes (w/ Flashcards)

For the reaction NH₃ + NO → N₂ + H₂O, identify the reactants, products, and their coefficients once the equation is balanced.

Reactants: 4NH₃ and 6NO; products: 5N₂ and 6H₂O

Fill in the blank with the correct number to balance the equation: ___KClO₃ → 2KCl + 3O₂.

2

A chemical equation is shown:

C₂H₄ + O₂ → CO₂ + H₂O

According to the law of conservation of mass, how many atoms of oxygen exist in the products of this reaction?

6

Which of the following laboratory procedures best illustrates the law of conservation of mass?

 Synthesizing 36 g of H₂O plus leftover reactants by combining 4 g of H₂ and 32 g of O₂

Match each subscript symbol to its correct meaning.

Match	Term	Definition
	(g)	A) Aqueous solution
	(l)	B) Gas
	(aq)	C) Liquid

1. B

2. C

3. A

An unbalanced chemical equation is shown:

H₂O₂ → 2H₂O + O₂

Which of the following statements explains why the equation is not balanced?

Two H₂O₂ molecules should decompose to form the given products.

Which chemical equation correctly represents the reaction that takes place when nitrogen gas and hydrogen gas are formed as ammonia decomposes?

2NH_3(g) → N_2(g) + 3H_2(g)

The reaction CO_2(g) → C_(s) + O_2(g) is a decomposition reaction.

True

Which of the following is a synthesis reaction?

 SO₃ + H₂O → H₂SO₄

What is true of a decomposition reaction?

 The addition of energy in the form of heat or electricity is often required.

A synthesis reaction can be identified because it involves more than one reactant forming one compound as the product.

True

Which of the following is a single replacement reaction?

 Fe + 3NaBr → FeBr₃ + 3Na

When HNO₃ and Au are mixed together, what do you expect to happen, and why?

No reaction, because Au is lower on the activity series and cannot replace H

A single replacement reaction is a reaction in which one element replaces a similar element within a compound.

True

The table shows the nature of reactants and products formed in a certain type of chemical reaction.

Nature of Reactants and Products

Reactants	Products
Metal + Ionic compound	Metal + Ionic compound

Which of the following is true about the type of chemical reaction?

It is a single replacement reaction, and the cations in the two ionic compounds are different.

When Pb and AlCl₃ react together, lead (Pb) can replace aluminum (Al) in the compound because lead is lower on the activity series.

False

Potassium hydroxide (KOH) reacts with sulfuric acid (H₂SO₄) to produce potassium sulfate (K₂SO₄) and water.

What best describes this reaction?

A double replacement reaction occurs because potassium ions bond with sulfate ions to form a salt.

In a redox reaction, the oxidizing agent gains electrons.

True

All redox reactions form ionic bonds.

False

Why are redox reactions used in batteries?

 The movement of electrons creates an electric current.

What does it mean when an element is reduced?

 It gains electrons, reducing its overall charge.

In which of the following reactions is chlorine (Cl) oxidized?

 Br₂ + 2Cl⁻ → Cl₂ + 2Br⁻