Acids and Bases

Question 1

What are Acids

Answer 1

Acids are compounds that release hydrogen ions (H+) when they dissolve in water

Question 2

What are Strong Acids (2)

Answer 2

• Found in the lab or a car battery = dangerous to touch/eat
• Corrosive - damage other materials

Question 3

What are Weak Acids (2)

Answer 3

• Found in everyday items such as food & skincare products
• Safe to handle these

Question 4

What are the 3 Main Lab Acids?

Answer 4

• Hydrochloric Acid - HCl
• Sulphuric Acid - H2SO4
• Nitric Acid - HNO3

Question 5

What are Bases?

Answer 5

Bases release hydroxide ions (OH-) when they dissolve in water

Question 6

What are Strong Bases/Alkali? (2)

Answer 6

• Alkali used to clean labs, or bleach, are dangerous to touch
• Caustic - burn skin & damage materials

Question 7

What are Weak Bases/Alkali? (3)

Answer 7

• Found in soaps and other cleaning materials, and antacids to treat digestion
• Safe to handle
• Feel soapy

Question 8

What is the Difference Between a Base and a Alkali?

Answer 8

If a base dissolves in water, it is called an alkali

Question 9

What are the Main Base/Alkali we use in the lab?

Answer 9

• Sodium hydroxide - NaOH
• Potassium hydroxide - KOH
• Calcium Hydroxide - Ca(OH)2

Question 10

What is the Ph of a Strong Acid?

Question 11

What is the Ph of a Weak Acid?

Question 12

What is the Ph of a Strong Base?

Question 13

What is the Ph of a Weak Base?

Question 14

What is a Neutralisation Reaction? (2)

Answer 14

When an acid and base are mixed together, a chemical reaction occurs

• The acid & base cancel each others effect.

Question 15

What is the Neutralisation Equation?

Answer 15

Acid + Base –> Salt + Water

Question 16

What is the PH Scale? (2)

Answer 16

• The pH scale is used to measure the strength of an acid or a base
• The scale is from zero (strongest acid) to 14 (strongest base)

Question 17

What are Indicators?

Answer 17

Indicators are dyes that change colour, depending on whether they are in an acid or in a base.

Question 18

What is Litmus Paper?

Answer 18

Indicators are dyes that change colour, depending on whether they are in an acid or in a base.

Ex Base in Red Litmus Turns Blue, and Acid in Blue Litmus turns Red

Question 19

What is Phenolphtalein (3)

Answer 19

• Colourless in acidic/neutral solution
• Pink in alkaline solution
• Can’t show strength of acid/alkali

Question 20

What is the Definition of a Salt?

Answer 20

Ionic compounds that consist of one metal ion and one non-metal ion

Question 21

What are the three equations/ways of making salt?

Answer 21

1) Acid + Base → Salt + Water
2) Acid + Metal → Salt + Hydrogen
3)
Acid + Metal Carbonate → Salt + Water + Carbon dioxide

Question 22

What is Collision Theory?

Answer 22

For a reaction to occur, particles must collide with sufficient energy.

Question 23

What is a Reaction Rate?

Answer 23

The speed at which a chemical reaction occurs.

Question 24

What are the Three Ways we can increase number of collisions?

Answer 24

1) ↑ temperature = ↑ kinetic energy of particles = ↑ movement of particles = ↑ collisions

2) ↑ concentration = ↑ particles per unit volume = ↑ collisions

3) ↑ surface area = ↑ amount of surface available for collision = ↑ collision rate