Classifying Chemical Reactions Slide

Question 1

Combination Reaction

Answer 1

Occurs when two reactants combine to form a single product. Important in industry. Represented by the generalized equation: X + Y → XY.

Question 2

Combination Reaction example:

Answer 2

Hydrogen gas + Chlorine gas → Hydrogen chlorid

Question 3

Decomposition Reaction

Answer 3

When a single reactant breaks apart to form several products, the reactant is said to decompose. Represented by the generalized equation: XY → X + Y.

Question 4

Decomposition Reaction example:

Answer 4

Carbonic acid → Water + Carbon dioxide

Question 5

Examples of Combination Reactions

Answer 5

Hydrogen gas + Chlorine gas → Hydrogen chloride

Copper carbonate → Copper oxide + Carbon dioxide

Question 6

Examples of Decomposition Reactions

Answer 6

• Carbonic acid → Water + Carbon dioxide
• Copper carbonate → Copper oxide (black solid) + Carbon dioxide (odorless gas)

Question 7

Bases

Answer 7

A base is a substance that produces hydroxide (OH-) ions when dissolved in water. The solution formed is referred to as being alkaline. Bases and alkaline solutions have a pH greater than 7 and can be just as dangerous as acids, such as NaOH, Ammonia, Soap, and Shampoo.

Question 8

Neutralization

Answer 8

Occurs when an acid reacts with a base.

An acid is any substance that releases hydrogen ions (H+) when dissolved in water. Acids have a pH of less than 7 and vary in strength from very safe to highly corrosive, such as HCl, HNO3, and H2SO4.

Question 9

Characteristics of Acids and Bases

Answer 9

• Acids release H+ ions in water
• Bases release OH- ions in water
• Acids have pH < 7, bases have pH > 7
• Both can be highly corrosive and dangerous

Question 10

Neutralization Reaction

Answer 10

When an acid and a base are mixed together, they can neutralize each other. This is because the hydrogen ions (H+) from the acid react with the hydroxide ions (OH-) from the base to form water (H2O). The resulting solution is neutral with a pH of 7.

Question 10

Equation for Neutralization

Answer 10

Acid + Base → Salt + Water
This shows the general balanced equation for a neutralization reaction, where the acid and base react to form a salt compound and water.

Question 11

Examples of Acid-Base Reactions

Answer 11

• Sulfuric acid + Magnesium hydroxide → Magnesium sulfate + Water
• H2SO4 + Mg(OH)2 → MgSO4 + 2H2O

Question 12

Acid + Base → Salt + Water

Answer 12

For example, hydrochloric acid (HCl) reacts with potassium hydroxide (KOH) to form potassium chloride (salt) and water.

Question 13

Acid + Metal Reactions

Answer 13

Acids react with metals to produce a salt and hydrogen gas. The general equation for this type of reaction is:
Acid + Metal → Salt + Hydrogen Gas

Question 14

Example of Acid-Metal Reaction

Answer 14

Hydrochloric acid (HCl) + Zinc (Zn) → Zinc chloride (ZnCl2) + Hydrogen gas (H2)

Question 15

Acid + Metal Reactions

Answer 15

Acids react with metals to produce a salt and hydrogen gas. The general balanced equation is:
Acid + Metal → Salt + Hydrogen Gas

Question 16

Example: Hydrochloric Acid and Magnesium

Answer 16

Hydrochloric acid (HCl) + Magnesium (Mg) → Magnesium chloride (MgCl2) + Hydrogen gas (H2)

Question 16

Nitric Acid and Calcium (acid +Metal–> Hydrogen Gas)

Answer 16

Nitric acid (HNO3) + Calcium (Ca) → Calcium nitrate (Ca(NO3)2) + Hydrogen gas (H2)