Vapour pressure of system depends upon intermolecular forces of interaction. Greater the interaction, larger will the vapour pressure, more will be the boiling point.
Answer 1:
CH4 stands for methane and CH3Cl named as chloromethane. In methane, all the valances of C atom is satisfied by hydrogen. Due to this, it has zero dipole moment. While, in case of CH3Cl, one of the valance is satisfied by an electronegative element i.e. Cl. Due to this, it acquires a polar character. Also, it has a net dipole moment. Due to this, CH3Cl exhibits dipole-dipole intermolecular force of attraction, which is absent in CH4. Hence, CH3Cl has lower vapor pressure as compared to CH4.
Answer 2:
H2CO is named as formaldehyde, while CH3OH is named as methyl alcohol. In case of methyl alcohol, hydrogen atom (an electropositive atom) is bonded to oxygen (a highly electronegative element). This is absent in case of formaldehyde. Due the this, methyl alcohol as greater polarity as compared to formaldehyde. Due the greater polarity, vapour pressure of CH3OH is less as compared to H2CO.
Answer 3:
<span>CH3CH2CH2OH is named as propanol or propyl alcohol. Propyl alcohol, has longer chain length as compared to methyl alcohol (CH3OH). Both of this compounds has a polar character due to presence of -OH functional group. However, due to long chain of propyl alcohol, polar character increases. This can be attributed the +I effect of CH3 group. Due to this, intermolecular forces of interaction are higher in propanol, thereby decreasing its vapor pressure as compared to methanol. </span>
Answer:
(C) Mass of KCl(s), mass of H20, initial temperature of the water, and final temperature of the solution
Explanation:
molar enthalpy of solution of KCl(s) is heat evolved or absorbed when one mole of KCl is dissolved in water to make pure solution . The heat evolved or absorbed can be calculated by the following relation.
Q = msΔt where m is mass of solution or water , s is specific heat and Δt is change in temperature of water .
So data required is mass of water or solution , initial and final temperature of solution , specific heat of water is known .
Now to know molar heat , we require mass of solute or KCl dissolved to know heat heat absorbed or evolved by dissolution of one mole of solute .
Answer: 7.608 x 10∧23
Explanation:
Using Avogadro's Number;
1 mole of Phosphorus (P4) molecule contains 6.02 x 10∧23 molecules.
∴ 0.316 mole of Phosphorus (P4) will contain; 0.316 x 6.02 x 10∧23 =
1.902 x 10∧23 molecules.
1 molecule of Phosphorus (P4) is made up of 4 atoms.
∴ 1.902 x 10∧23 molecules Phosphorus (P4) will contain :
1.902 x 10∧23 x 4 = 7.608 x 10∧23 atoms
0.316 mole of phosphorus contains 7.608 x 10∧23 atoms.
