Answer:
2.256 moles of oxygen atoms
Explanation:
CaCo3 is calcium carbonate
every mole of calc carb has 3 moles of O atoms
.752 moles of this has 3 times as many moles of Oxygen atoms
According to Raoult's law the relative lowering of vapour pressure of a solution made by dissolving non volatile solute is equal to the mole fraction of the non volatile solute dissolved.
the relative lowering of vapour pressure is the ratio of lowering of vapour pressure and vapour pressure of pure solvent

Where
xB = mole fraction of solute=?

p = 22.8 torr

mole fraction is ratio of moles of solute and total moles of solute and solvent
moles of solvent = mass / molar mass = 500 /18 = 27.78 moles
putting the values




mass of glucose = moles X molar mass = 1.218 X 180 = 219.24 grams
Explanation:
The speed of molecules increases when temperature is increased as it will result in more number of collisions between the molecules. Thus, there will be increase in kinetic energy of molecules and increase in the speed of solvent molecules.
Whereas on decreasing the temperature, the kinetic energy of molecules will decrease. This will result in less number of collisions between the molecules. Therefore, the speed of solvent molecules will slow down.