A COMBUSTION reaction occur when a substance ...........................................
Combustion reaction is also known as burning. It occurs when an hydrocarbon react with oxygen to yield carbon dioxide, water and energy in the form of light and heat. Combustion reaction can not take place in the absence of oxygen.
Answer: The vapor pressure of methanol solution at 298K is 107.12 torr
Explanation:
As the relative lowering of vapor pressure is directly proportional to the amount of dissolved solute.
The formula for relative lowering of vapor pressure will be,
where,
= relative lowering in vapor pressure
i = Van'T Hoff factor = 1 (for non electrolytes)
= mole fraction of solute =
Given : 38.5 g of urea is present in 142 g of methanol
moles of solute (urea) =
moles of solvent (methanol) =
Total moles = moles of solute + moles of solvent = 0.64 + 4.4 = 5.04
= mole fraction of solute =
Thus the vapor pressure of methanol solution at 298K is 107.12 torr
V=0.650 L
c=0.505 mol/L
M(Na₂CO₃)=106.0 g/mol
the amount of substance of sodium carbonate is:
n(Na₂CO₃)=vc
the mass of sodium carbonate is:
m(Na₂CO₃)=n(Na₂CO₃)M(Na₂CO₃)
m(Na₂CO₃)=vcM(Na₂CO₃)
m(Na₂CO₃)=0.650*0.505*106.0=34.7945 g
The trend is that as you move along the period (from left to right in a row) the atomic radius decreases.