Given the following heats of formation. Calculate the heat of combustion of each compound in kJ mole -1 . The product in each case
will be CO 2(g) and H 2 O (l) .
(a) ethane, C 2 H 6(g) , -107 kJ mole -1
(b) acetylene, C 2 H 2(g) , +227 kJ mole -1
(c) benzoic acid, C 7 H 6 O 2(s) , -390 kJ mole -1

Acetic acid, hc2h3o2, dissolves and completely dissociates in water and a solvation sphere of water molecules forms around the ions. this solute-solvent interaction

Construct the hypothetical phase diagram for metals a and b between room temperature (20c) and 700c, given the following information: * the melting temperature of metal a is 480c. • the maximum solubility of b in a is 4 wt% b, which occurs at 420c. • the solubility of b in a at room temperature is 0 wt% b. • one eutectic occurs at 420c and 18 wt% b–82 wt% a. • a second eutectic occurs at 475c and 42 wt% b–58 wt% a. • the intermetallic compound ab exists at a composition of 30 wt% b–70 wt% a, and melts congruently at 525c.• the melting temperature of metal b is 600c. • the maximum solubility of a in b is 13 wt% a, which occurs at 475c. • the solubility of a in b at room temperature is 3 wt% a.

As air becomes more dense, (select all that apply) o. air weighs less o. gas molecules are closer together o. air is colder o. air weighs more o. gas molecules are further apart o. air is hotter