Determining the Enthalpy of Neutralisation for Three Acids

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Determining the Enthalpy of Neutralisation for Three Acids

[IMAGE]Determine the Enthalpy of Neutralisation for the following

there Acids, H2SO4, HNO3 andH2SO4

Introduction

Acid and bases have a very important property that is that they are

able to cancel each other out when mixed together in the right

proportions, this reaction is called a neutralisation reaction, which

can be an exothermic reaction .

The standard enthalpy of neutralisation is the heat absorbed per mole

when an acid and a base react to form water under standard conditions.

In this experiment I will be investigating the values for enthalpy of

neutralisation of the three strong acids (HCl, HNO3 andH2SO4)

Scientific Background information

As explained before, neutralisation happens between an acid and a

base. Neutralisation is the formation of water from hydrogen and

hydroxide ions

H30+(aq) + OH-(aq) Ã 2H20(aq)

According to Arrhenius’ theory ‘neutralisation occurs because equal

mols of hydrogen ions in the acid are equal to the mols of hydroxide

ions in the base so the two react completely to form waterÂ’*1.

Neutralisation of HCl and NaOH:

NaOH(aq)Â Â Â Â Â Â Â Â +Â Â Â Â Â Â Â Â Â HCl(aq)Â Â Â Â Â Â Â Â Â Â Â Â Â Ã Â Â Â Â Â Â Â Â Â Â Â Â NaCl(aq) Â Â Â Â Â Â + Â Â Â H2O(l).

Neutralisation of HNO3 and NaOH

NaOH(aq) + HNO3(aq) Ã NaNO3(aq) +

H20(l).

Neutralization of H2SO4

NaOH(aq) + H2SO4 Ã Na2SO4(aq) + H20(l)

The enthalpy of neutralisation for strong acids are similar, because

‘strong acids fully disassociate in water therefore all hydrogen ions

and all hydroxide ions react to from water moleculesÂ’*2- taken from

Ramsden A level Chemistry

However enthalpy of neutralisation for H2SO4 would be different

compared to the the enthalpy of neutralisation for the other two

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