Sifat zat yang bekerjasama dengan gampang atau sukarnya zat untuk bereaksi kimia disebut​

Iknow the answer is a but i don't know why

Compared with the freezing-point depression of a 0.01 m c6h12o6 solution, the freezing-point depression of a 0.01 m nacl solution is

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.