G8 Synthesis and Analysis - Acids

Gapfill exercise

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   acid      below      bubbles      carbon dioxide      completely      concentrated      hydrogen      ink      ions      molecular      pH      salt      salts      slightly      water      wax   
Acids are very dangerous when they are . Dilute acids are less dangerous.
Organic acids are - made from a group of atoms joined together. The acidity comes from the in the -COOH group.
Inoganic acids come from mineral sources and are widely used in industry.
The measure of acidity is the .
pH 1 is a strong acid, pH7 is neutral and pH 14 is a strong alkali.
Indicators are chemicals that change colour with acids and alkalis. Litmus is an example of an indicator.

Acids with metals.
Acids react with metals to make and hydrogen gas.

acid + metal -> salt +

but not all metals act like this. Metals lead in the reactivity series do not form salts with acids.

Chemical etching uses acids.
The sheet of metal is covered in .
The artist scrapes away some wax to make a drawing.
The plate is dipped in which reacts with the metal where the wax has been scratched away.
The artist brushes away any hydrogen .
The plate is removed and rinsed.
The plate is covered in which flows into the grooves made by the acid.

Acids with metal oxides and metal hydroxides.
Acids react with metal oxides and hydroxides to make a and water.

acid + metal oxide -> salt +

Acids with metal carbonates
Acids react with metal carbonates to make a salt, water and gas.

acid + metal carbonate -> salt + + carbon dioxide

What makes something an acid?
Acids do not mix with water - they react with it to produce hydrogen . All acids have hydrogen in their formula.
Strong acids ionise in water, weak acids only ionise - only some of the molecules are ionised.