ACIDS AND BASES. Acids Acidic solutions contain water and hydrogen ions (H+)

ACIDS AND BASES

Acids

Acidic solutions contain water and hydrogen ions (H+)

Acids

Acidic solutions contain water and hydrogen ions (H+)

When dilute acidic solutions react, it is the hydrogen ions that are involved in the reaction.

Acids

Acidic solutions contain water and hydrogen ions (H+)

When dilute acidic solutions react, it is the hydrogen ions that are involved in the reaction.

Common acids are:- Hydrochloric acid (HCl)

Acids

Acidic solutions contain water and hydrogen ions (H+)

When dilute acidic solutions react, it is the hydrogen ions that are involved in the reaction.

Common acids are:- Hydrochloric acid (HCl)- Nitric Acid (HNO3)

Acids

Acidic solutions contain water and hydrogen ions (H+)

When dilute acidic solutions react, it is the hydrogen ions that are involved in the reaction.

Common acids are:- Hydrochloric acid (HCl)- Nitric Acid (HNO3)- Sulfuric Acid (H2SO4)

Acids

Acidic solutions contain water and hydrogen ions (H+)

When dilute acidic solutions react, it is the hydrogen ions that are involved in the reaction.

Common acids are:- Hydrochloric acid (HCl)- Nitric Acid (HNO3)- Sulfuric Acid (H2SO4) - Citrus fruits are acidic, as well as carbonated

drinks (like coke).

Bases

Bases are substances that neutralise acids by forming water and a salt.

Bases

Bases are substances that neutralise acids by forming water and a salt.

Common bases are:- Sodium Hydroxide (NaOH)

Bases

Bases are substances that neutralise acids by forming water and a salt.

Common bases are:- Sodium Hydroxide (NaOH)- Calcium hydroxide ( Ca(OH)2 ) or

limewater

Bases

Bases are substances that neutralise acids by forming water and a salt.

Common bases are:- Sodium Hydroxide (NaOH)- Calcium hydroxide ( Ca(OH)2 ) or

limewater- Ammonia solution (NH3)

Bases

Bases are substances that neutralise acids by forming water and a salt.

Common bases are:- Sodium Hydroxide (NaOH)- Calcium hydroxide ( Ca(OH)2 ) or

limewater- Ammonia solution (NH3) Bases have hydroxide ions (OH-)

Neutral Substances

Some substances, such as salt (Sodium Chloride) dissolve in water forming solutions which are neutral.

Neutral Substances

Some substances, such as salt (Sodium Chloride) dissolve in water forming solutions which are neutral.

Pure water is neutral

The pH scale

Some acids are stronger than others; strong acids produce the highest concentration of hydrogen ions.

The pH scale

Some acids are stronger than others; strong acids produce the highest concentration of hydrogen ions.

Strong bases produce high concentrations of hydroxide ions.

The pH scale

Some acids are stronger than others; strong acids produce the highest concentration of hydrogen ions.

Strong bases produce high concentrations of hydroxide ions.

The same applies for weak acids/weak bases having low concentrations of particular ions.

The pH scale

Some acids are stronger than others; strong acids produce the highest concentration of hydrogen ions.

Strong bases produce high concentrations of hydroxide ions.

The same applies for weak acids/weak bases having low concentrations of particular ions.

The pH scale is used to measure how acidic or basic a solution is.

The pH scale

Acidic solutions have pH of less than 7

The pH scale

Acidic solutions have pH of less than 7 Basic solutions have pH of more than 7

The pH scale

Acidic solutions have pH of less than 7 Basic solutions have pH of more than 7 Neutral solutions are 7

The pH scale

Acidic solutions have pH of less than 7 Basic solutions have pH of more than 7 Neutral solutions are 7

Red and blue litmus paper can be used to indicate whether the solution is an acid or a base.

The pH scale

Acidic solutions have pH of less than 7 Basic solutions have pH of more than 7 Neutral solutions are 7

Red and blue litmus paper can be used to indicate whether the solution is an acid or a base.

Red – turns blue in a base Blue – turns red in an acid

The pH scale

Pour 1cm of solution into your 5 test tubes

Using red or blue litmus paper, drop the paper into the test tubes and see what colours they change to.

Write down what solution is an acid or base

pH scale

Using your solutions from before… Add universal indicator to each of your

solutions and see what number pH they are.

Write it down in your books.