This question is about tartaric acid, a hydrated dicarboxylic acid. Its formula can be represented as H2Y⋅xH2OH_2Y \cdot xH_2OH2Y⋅xH2O.
A 2.10 g2.10\text{ g}2.10 g sample of H2Y⋅xH2OH_2Y \cdot xH_2OH2Y⋅xH2O contains 1.40 g1.40\text{ g}1.40 g of oxygen by mass. The sample burns completely in air to form 2.20 g2.20\text{ g}2.20 g of CO2\text{CO}_2CO2 and 0.900 g0.900\text{ g}0.900 g of H2O\text{H}_2\text{O}H2O. Show that the empirical formula of the hydrated tartaric acid is C4H8O7\text{C}_4\text{H}_8\text{O}_7C4H8O7.
A 4.20 g4.20\text{ g}4.20 g sample of H2Y⋅xH2OH_2Y \cdot xH_2OH2Y⋅xH2O (Mr=168.0M_{\text{r}} = 168.0Mr=168.0) is heated to constant mass. The anhydrous H2YH_2YH2Y that remains has a mass of 3.75 g3.75\text{ g}3.75 g. Show, using these data, that the value of x=1x = 1x=1.
Figure 5 shows the structure of H2YH_2YH2Y:
Complete this IUPAC name for H2YH_2YH2Y:
____________________ butanedioic acid\text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ butanedioic acid}____________________ butanedioic acid [1/mark]
State the number of peaks you would expect in the 13C NMR{}^{13}\text{C}\text{ NMR}13C NMR spectrum for H2YH_2YH2Y. [1/mark]