Answer:
Potassium chloride > Butanol >Propane > Ethane
Explanation:
Water is a polar solvent and it is likely to dissolve polar molecules.
KCl is ionic in nature and is completely polar and the solubility of the salt, potassium chloride is the highest.
Butanol can form hydrogen bonding with the water despite having a carbon chain. Thus, butanol will be at second.
Taking about, ethane and propane, both are non polar and least likely to dissolve in water. But, the extent of the London forces increases with the increase in the molecular weight. So, propane will dissolve faster than ethane.
The order is:
Potassium chloride > Butanol >Propane > Ethane
True
Pressure is the force per unit area on an object. The force in the case of air pressure is the weight of the air molecules; therefore, the air pressure is essentially due to gravity pulling down air molecules.
It will double
Key
P = pressure of the gas
n= number of moles of the gas
V= volume of the gas
R = the gas constant
T= absolute temperature of the gas
If V is halved when n and T remain the same
Molality of the solution is defined as the number of moles of a substance dissolved divided by the mass of the solvent:
Molality = number of moles / solvent mass
From the concentration of 39% (by mass) of HCl in water, we construct the following reasoning:
in 100 g solution we have 39 g hydrochloric acid (HCl)
number of moles = mass / molecular weight
number of moles of HCl = 39 / 36.5 = 1.07 moles
solvent (water) mass = solution mass - hydrochloric acid mass
solvent (water) mass = 100 - 39 = 61 g
Now we can determine the molality:
molality = 1.07 moles / 61 g = 0.018
Divide by the molar mass of HCl which is 36.5g/mol grams cancels out and you are left with 1.99 mol.
