Methanoic acid and ethanoic acid are weak acids.

1. (a)What does the term weak mean, when applied to acids?[1]
2. (b)(i)Methanoic acid, HCO2H, reacts with magnesium powder. Construct the equation for this reaction.[1]
3. (b)(ii)State and explain how the rate of this reaction changes when the experiment is repeated using a piece of magnesium ribbon with the same mass as the powder. All other conditions stay the same. Include in your answer ideas about collisions between particles.[2]
4. (c)Methanoic acid reacts with propanol, C3H7OH, to form an ester. Name and draw the structure of this ester, showing all of the atoms and all of the bonds. name structure[2]
5. (d)(i)Ethanoic acid is present in vinegar. Name the organic compound which is converted to ethanoic acid when vinegar is made.[1]
6. (d)(ii)What type of chemical reaction is this?[1]
7. (e)(i)The table shows some properties of four carboxylic acids. carboxylic acid | formula | density in g/cm³ | boiling point in °C methanoic acid | HCO₂H | 1.22 | 101 ethanoic acid | CH3CO2H | | 118 propanoic acid | C2H5CO2H | 0.99 | 141 butanoic acid | C3H7CO2H | 0.96 | 164 Predict the density of ethanoic acid. .................................................... g/cm³[1]
8. (e)(ii)Describe and explain the change in the boiling point as the number of carbon atoms in a molecule increases.[1]