Question

8). Surface tension: A.is tendency of liquid to maximize surface area B. decreases with decreasing strength of intermolecular force C. increases with decreasing strength of intermolecular force D. all are correct

9) Viscosity: A. decreases with size of molecules B. decreases with decreasing strength of intermolecular force C. increases with decreasing temperature D. all are correct

10) Adding salt to water does what? A. lowers freezing point C. increases ion-dipole interactions B. increases surface tension D. all are correct

11) What happens to the vapor pressure of a substance when its surface area is increased at constant temperature? A. vapor pressure increases C. vapor pressure remains the same B. vapor pressure decreases D. answer is not listed

12) Place the following compounds in order of decreasing boiling point. • CH3CH2OCH3 II. HOCH2CH2CH2OH • III. CH3CH2CH2OH IV. CH3CH2CH3 A. II>III>I>IV B. III>II>IV>I C. III>II>I>IV D. III>I>II>IV

13) Which of the following compounds will be most soluble in pentane (C5H12)? A. pentanol (CH3CH2CH2CH2CH2OH) B. benzene (C6H6) C. acetic acid (CH3CO2H) D. ethyl methyl ketone (CH3CH2COCH3)

Answer 1

8]

Answer is B ---> decreases with decreasing strength of intermolecular force

9]

Answer is D --> All are correct

10]

Answer is D ---> all are correct

11]

Answer is C --> vapour pressure remains same

Vapoure pressure depends only on temperature

12]

Answer is A ---> II>III>I>IV

ii ---> hydrogen bonding (two OH groups)

iii ---> hydrogen bonding ( one OH group)

i ---> dipole -dipole interactions

iv ---> vanderwaasl force

Hydrogen bonding > dipol -dipole > vanderwaals

13]

Answer is B --> benzene

pentane is non polar solvent

Benzene also nonpolar solvent , like dissolves in like only