Question

Can you help me with the question 5&6? Given data of group 9 only

In this lab, the temperature of chemicals before chemical change and after chemical change was collected and thus, weather bonds were broken or created was determined. To do this a calorimeter was used; a calorimeter can help us measure heat of chemical reaction Data: Grou Tria Volum Volum mol H20 mol 1e H20 eEtOH Ethanolfraction aT H20 22. 23. 0.9 22. 24. 2.2 22. 26. 4 22. 27. 5.1 23 29. 6.2 1 0.9 30.1 0.0499 2 3.05 22.2 0.169 3 7.07 22.2 0.3923 4 12.12 17.5 0.67258 79 1.10 5 19.97.5 27 2 420 18 12 10 12 20. 21. 1.7 2 9 19. 22. 2.7 9 19. 24.5.1 6 4 15 20. 28. 8.2 5 25 22. 26. 41 Grou Tria Volum Volum mol H20 mol mol H20 0.80421 18. 3 Acetonitril fraction a T 6 14.210 0.39444444 0.1919 10620 0.55555555 22. 21-1.7 7 Discussion: Layout View Sec 1 Pages: 1 of 2 Words: 285 of 304 |脹

Answer 1

Group	Trial	Volume H2O	Volume ethanol	Moles H2O	Moles ethanol	Mole fraction H2O	Ti	Tf	Delta T
9	1	0.9	30.1	0.0499	0.5155	0.08826	22.5	23.4	0.9
	2	3.05	22.2	0.169	0.3802	0.3077	22.7	24.9	2.2
	3	7.07	22.2	0.3923	0.3802	0.50783	22.7	26.7	4
	4	12.12	17.5	0.67258	0.2958	0.69454	22.8	27.9	5.1
	5	19.9	7.5	1.10	0.1285	0.89734	23	29.2	6.2
	6	14.2	10	0.394444444	0.1919 (acetonitrile)	0.804	21.3	18.3	-3

1) The mole fraction of trial 5 releases maximum a heat since heat of reaction or enthalpy change is directly proportational to temperature and the temperature change in trial 5 is maximum.

In order for a solute to be soluble in a particular solvent, 3 things must be considered. 1st the intermolecular force holding the solvent molecules together must be broken (requires energy). 2nd the intermolecular forces holding the solute together must be broken (requires energy). Finally the solute & solvent can interact through whatever forces available (bond formation requires energy) called solvation energy. Generally withincrease in temperature the solubility increases.

q = m*C*dT where, q= heat capacity; m= mass; C= specific heat capacity; dT =change in temp.

C for ethanol is 2.460J/gC^o

Mass	dT	q
23.749	0.9	52.58
17.5158	2.2	94.795
17.5158	4	172.55
13.8075	5.1	173.23
5.9175	6.2	90.2537