Physics - Acids, bases and neutralusation

Give examples of acids

oranges, vinegar lemon, milk, pineaple, mouth wash, stomach acid and battery acid

Give examples of bases

cleaning products, backing soda, rust and sanitizer

What are the properties of an acid?

Acids taste sour, feel rough on the skin, turn blue litmus paper, have a pH of less than 7, and can be dangerous to taste or feel

What are the properties of a base?

Bases taste bitter and feel slippery red to blue, has a pH that is higher than 7

What is neutralisation?

A reaction that occurs when acids and bases react together.

What'll the pH of a substance be after neutrralisation has taken place?

The resultant pH may vary based on the strength of the base and acid reactants

What happens when a base reacts with an acid?

When a base reacts with an acid - solution becoms less acidic or neutral.

What happens when an acid reacts with a base?

When an acid reacts with a base - the solution becomes less basic or neutral.

What acids are commonly found in the lab, and what should be noted?

1. hydrochloric acid - HCl

2. Nitric acid - HNO₃

3. Sulphuric acid - H₂SO₄

NB! Non-metal oxides tend to be acidic (low pH)

What bases are commonly found in the lab, and what should be noted?

1. Magnesium oxide - MgO

2. Sodium hydroxide - NaOH

3. Calcium carbonate - CaCO₃

NB! metal oxides, metal hydroxides and metal carbonates tend to be basic (high pH)

What is the general equation for neutralisation?

Acid + base → salt + water

What is the general equation for neutralisation, also known as, and what should the base always start with?

It is referred to as exchange reaction and the base should always start with the metal.

What are the neutralisation reactants?

Acid and metal oxide

Acid and metal hydroxide

Acid and metal carbonate (carbon dioxide is produced)

What is the general equation for acid + metal oxide?

Acid + metal oxide → salt + water

What is the general equation for acid + metal hydroxide?

Acid + metal hydroxide → salt + water

What is the general equation for acid + metal carbonate?

Acid + metal carbonate → salt + water + carbon dioxide

When acid mixes with metal oxide what contributes the H atom and what contributes the O atom?

Acid contributes the H- atom and the base contributes the O atom to make water (H₂O) what is left will make salt.

What is salt?

Salt is a crystalline product that is made of a metal and non-metal

How is acid rain formed.

1. burning of fossil fuels + oils

2. release CO₂ and SO₂ gas

3. SO₂ and CO₂ react with H₂O

Give the two chemical equations for acid rain.

CO₂ + H₂O → H₂Co₃ (carbonic acid)

SO₂ + H₂O → H₂SO₃ (Sulphurous acid)

What do farmers use to protect the soil from the acid rain?

Limestone (CaCO₃) is used in agriculture to make the soil less acidic