AIM:-
To investigate how heat is given out in neutralizing sodium hydroxide
(NaOH) using different concentrations of Hydrochloric Acid.
Background Information:-
Substances that neutralize acids are called alkalis. An acid is a substance that forms hydrogen ions (H+ ) when placed in water. It can also be described as a proton donor as it provides H+ ions. An example of an acid is hydrochloric acid (HCl), Sulphuric acid (H2SO4) etc. An alkali is a soluble base and forms hydroxyl ions (OH-) when placed in water. It can be called a proton acceptor and will accept hydrogen ions to form H2O. An example of an alkali is Sodium Hydroxide
(NaOH).
Neutralization Reaction:-
[IMAGE]Acid + Alkali Salt + Water
[IMAGE]Hydrochloric acid + Sodium Hydroxide Sodium
Chloride + Water
[IMAGE]HCl(aq) + NaOH(aq) NaCl(aq) + H2O(l)
[IMAGE]H+ (aq) + Cl- (aq) + Na+ (aq) + OH- (aq) Na+
(aq) + Cl- (aq) +H+ + OH-
[IMAGE]The above is an example of a neutralization reaction, involving an acid and an alkali. The result is a salt and water. In every neutralization reaction, the metal in the alkali (Na+ here) takes the place oh the hydrogen in the acid, forming a metal compound called a salt. The hydrogen and the hydroxide ions react to form water. As bonds are made this is an exothermic reaction so heat will be given out and this will be shown as an increase in temperature. The chemical energy will be negative ( H is minus).
APPRATUS/MATERIALS:-
1. Polystyrene cup
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2. Measuring cylinder
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3. Thermometer (0. C to 50. C )
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4. Test Tubes
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5. Sodium Hydroxide
[IMAGE]
6. Hydrochloric Acid
Hydrogen atom
Hydrochloric Acid molecule
[IMAGE][IMAGE]
Chlorine Atom
[IMAGE][IMAGE]
7. Dropper
8. Goggles
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9. Teat Tube stand
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PREDICTION:-
I think that the acid of higher concentration