I need help with this question from my gen chem lab, I know it may seem simple b
ID: 856030 • Letter: I
Question
I need help with this question from my gen chem lab, I know it may seem simple but the Chemistry program here at OU is awful and does not teach they simply expect things. I really could use a description with the answer to help me with the rest of my lab report. Thank you!
Calculate the molar enthalpies of reaction for the following reactions using the enthalpies of formation shown in the table.
a. H+(aq) + OH-(aq) ---> H2O(l)
b. Mg(s) + 2H+(aq) ---> Mg2+(aq) + H2(g)
c. Ca(s) + 2H+(aq) ---> Ca2+(aq) + H2(g)
Table:
0.0
-229.9
Substance Standard Enthalpy of Formation (delta) H, kJ/mole H2O(l) -285.8 Mg2+(aq) -467.0 Sr2+(aq) -545.5 Ba2+(aq) -537.6 Ca2+(aq) -543.0 H+(aq)0.0
OH-(aq)-229.9
Explanation / Answer
a. H+(aq) + OH-(aq) ---> H2O(l)
DH= DH(H2O)-DH(H^+)-DH(OH^-1)
DH=-285.5-0-(-229.9)
DH=-55.6 KJ/MOLE
b. Mg(s) + 2H+(aq) ---> Mg2+(aq) + H2(g)
DH= DH(Mg^+2)- DH(H2)-DH(Mg)-2*DH(H^+)
DH= -467-0-0-2(0)
DH= -467KJ/MOLE
c. Ca(s) + 2H+(aq) ---> Ca2+(aq) + H2(g)
DH= DH(Ca^+2)- DH(H2)-DH(Ca)-2*DH(H^+)
DH= -543-0-0-2(0)
DH= -543KJ/MOLE