Answer:
A. 2NO + O2 -> 2NO2
B. 4Co + 3O2 -> 2Co2O3
C. 2Al + 3Cl2 -> Al2Cl6
D. 2C2H6 + 7O2 -> 4CO2 + 6H2O
E. TiCl4 + 4Na -> Ti + 4NaCl
The answer is 4. It can hold 4 sublevels as s.p,d,f and it holds 32 electrons
c) the salt solubility decreases with temperature.
Salts usually dissolve in water at a given temperature. When water cannot dissolve anymore salt at that same temperature, it is known as a saturation point. With most substances the solubility increases with increase in temperature. Same is the case for a salt like potassium nitrate. With increase in temperature the ability of it to dissolve in water increases. And so with decrease in temperature, the solubility decreases.
Potential energy and height; best guess;)