제가.. 영어가 후달려서 그러는지 강의열심히 들었는데 2번만 조금 끙끙대면서 생각해 보고 있구 다른건 어케 해야될지 전혀 모르겠어요 ㅠ
제가..학교에 친구도 없고 아는 선배도 없고 .. 그래서 물어볼 곳이 없어서 여기에 물어봅니다 능력자님들 좀만 도와주세요 ㅠ

1번.The SO42- in a 0.2057g sample was precipitated as BaSO4(s) by treatment with an excess of a solution that contained the Ba complex of EDTA, BaY2-. The liberated EDTA in the filtrate and washings required 31.79mL of 0.02644M Mg2+ solution. Express the results of this analysis in terms of percent Na2SO4. 답: 58.05%

2번.Combustion of a 0.3826g sample of a purified organic compound containing only C, H, and O resulted in the formation of 0.7823g of CO2 and 0.2402g of H2O. Calculate
(a) the percentages of C, H, and O in the sample. 답: 55.78% 6.97% 37.25%
(b) the empirical formula for the compound. 답: C2H3O(숫자는 다 작은첨자에요)

3번.The HgO in an impure 0.5214g sample of the mineral montroydite was brought into solution with an excess of KI.
Reaction: HgO(s) + 4I- + H2O = Hgl42-+ 2OH- (뒤쪽에 4는 아래첨자고 2는 위첨자겠지요?)
Calculate the percentage of HgO in the sample if 38.79mL of 0.0968M HCl were needed to titrate the liberated base.
답: 77.98%