Question

2. Data is shown where the saturation temperature has been found for dissolving 6.5 g of solid ammonium chloride (NH4CI) in various quantities of water. Mass of NH Cl used in all trials 6.5 g Total mass of H2O used 9.0 g (trial 1) Saturation temperature Solution concentration 16.0 g (trial 3) 28 °C 41 g/100 g H2O 12.0 g (trial 2) 58 °C 97 °C 72 g/100 g H2O a) Complete the data by calculating the solution concentration at 58 °C. 80- 70- grams NH Cl 100 g H2O 60- 50- 40- b) Graph the data 80 100 60 40 temperature °c 3. Name three sources of experimental error other than weighing that could be important in this experiment. Explain how each would influence the results. 20

Answer 1

The solution concentration of trial 2 is 54gm/100gm water.

the steps are as given = (100 X 6.5 )/12 = 54 gm.

b) for graph pl find the attachment.

	80
								97C and 72gm
	70
NH4Cl
gm/100gm water
	60
					54gm, 58C
	50
				41gm and 28C
	40
		20	40	50	60	70	80	100
			Temperature in C

3. sources of experimental error

a) the temperature of the solution may fluctuate as the reaction is endothermic when ammonium chloride is dissoleved in water.

b) accurate weighing of ammonium chloride.as this is hygroscopic in nature

c) proper stirring of the salt during dissolved.