"The statements in the following multiple choices deal with various aspects of the relationship between vapor pressure and inter
molecular forces. Choose the statement which is true. a) At a given temperature liquid NH3 has higher vapor pressure than liquid PH3. b) The average kinetic energy of boiling water molecules is higher on a mountaintop than it is at sea level. c) Large amounts of water have less vapor pressure than small amounts of water at the same temperature. d) CCl4 is more volatile than CBr4. e) Liquids have lower vapor pressures at high temperatures than they do at lower temperatures."
NH₃ is more polar molecule than PH₃ so inter-molucular attraction is greater in NH₃ ( hydrogen bond ) . Hence vapour pressure is low for NH₃ .
b ) false .
The average kinetic energy of boiling water molecules is lower on a mountaintop than it is at sea level. It is so because water boils at lower temperture on mountain and kinetic energy of molecules depends upon temperature .
c ) false
vapour pressure depends upon temperature .
d ) True
CCl4 is more volatile than CBr4
e ) false
vapour pressure increases as temperature increases.
In dilution we add distilled water to decrease the concentration of required sample from high concentration to lower concentration The law used for dilution: M₁V₁]Before dilution = M₂V₂] After dilution M₁ = 1.5 M V₁ = ? M₂ = 0.3 M V₂ = 500 ml 1.5 * V₁ = 0.3 * 500 ml so V₁ = 100 ml and it completed to 500 ml using 400 ml deionized water
