Year :
2017
Title :
Chemistry
Exam :
JAMB Exam
Paper 1 | Objectives
11 - 20 of 49 Questions
| # | Question | Ans |
|---|---|---|
| 11. |
For a general equation of the nature xP + yQ → mR + nS, the expression for the equilibrium constant is A. k [P]x [Q]y B. \(\frac{[P]^x [Q]^y}{[R]^m [S]^n}\) C. \(\frac{[R]^m [S]^n}{[P]^x [Q]^y}\) D. \(\frac{m[R] n[S]}{x[P] y[Q] }\) |
|
| 12. |
A given mass of gas occupies 2dm3 at 300k. At what temperature will its volume be doubled, keeping the pressure constant? A. 400k B. 480k C. 550k D. 600k |
|
| 13. |
The oxidation number of iodine in KIO3 is A. +7 B. +3 C. +5 D. +6 |
|
| 14. |
An isomer of C5H12 is A. 2–ethyl butane B. butane C. 2–methyl butane D. 2–methyl propane |
|
| 15. |
When few drops of concentrated trioxonitrate(V) acid is added to an unknown sample and wanned an intense yellow colouration is observed. The likely functional group present in the sample is A. NH2RCHCOOH B. CHO C. CO D. CNH2 Detailed SolutionXanthopreitic test for the presence of protein, when conc nitric acid is added to the drop, an intense yellow colouration is observed.It contains all the functional group of protein which includes the amino, alkanol and the carboxylic group. Adding few drops of conc HNO3 to a protein, gives an intense yellow colouration. It is called Xanthopreitic test. There is an explanation video available below. |
|
| 16. |
A sample of orange juice is found to have a PH of 3.80. What is the concentration of the hydroxide ion in the juice? A. 1.6 \(\times\) 10-4 B. 6.3 \(\times\) 10-11 C. 6.3 \(\times\) 10-4 D. 1.6 \(\times\) 10-11 |
|
| 17. |
Incomplete oxidation of ethanol yields A. CH3COOH B. CH3COCH3 C. CH3CH2OCH2CH3 D. CH3CHO Detailed SolutionC2H5OH → CH3CHO → CH3COOHEthanol.....oxidation Ethanal........Ethanoic Acid Primary alcohol oxidises to aldehyde and later to carboxylic acid. Secondary alcohol oxidises to ketones. Ethanol is an example of primary alcohol and primary alcohol can be oxidised to aldehyde and carboxylic acid. Wherein, incomplete oxidation of primary alcohol yields aldehyde also known as alkanal while complete oxidation of primary alcohol yields carboxylic acid. There is an explanation video available below. |
|
| 18. |
The salt formed from a weak acid and a strong base hydrolyzes in water to form A. A saturated solution B. an acidic solution C. a buffer solution D. an alkaline solution |
|
| 19. |
The ideal gas laws and equations are true for all gases at A. low pressures and lower temperatures B. low temperatures and high pressures C. high pressures and high temperatures D. low pressure and high temperatures |
|
| 20. |
When ΔH is negative, a reaction is said to be A. endothermic B. exothermic C. reversible D. ionic |
| 11. |
For a general equation of the nature xP + yQ → mR + nS, the expression for the equilibrium constant is A. k [P]x [Q]y B. \(\frac{[P]^x [Q]^y}{[R]^m [S]^n}\) C. \(\frac{[R]^m [S]^n}{[P]^x [Q]^y}\) D. \(\frac{m[R] n[S]}{x[P] y[Q] }\) |
|
| 12. |
A given mass of gas occupies 2dm3 at 300k. At what temperature will its volume be doubled, keeping the pressure constant? A. 400k B. 480k C. 550k D. 600k |
|
| 13. |
The oxidation number of iodine in KIO3 is A. +7 B. +3 C. +5 D. +6 |
|
| 14. |
An isomer of C5H12 is A. 2–ethyl butane B. butane C. 2–methyl butane D. 2–methyl propane |
|
| 15. |
When few drops of concentrated trioxonitrate(V) acid is added to an unknown sample and wanned an intense yellow colouration is observed. The likely functional group present in the sample is A. NH2RCHCOOH B. CHO C. CO D. CNH2 Detailed SolutionXanthopreitic test for the presence of protein, when conc nitric acid is added to the drop, an intense yellow colouration is observed.It contains all the functional group of protein which includes the amino, alkanol and the carboxylic group. Adding few drops of conc HNO3 to a protein, gives an intense yellow colouration. It is called Xanthopreitic test. There is an explanation video available below. |
| 16. |
A sample of orange juice is found to have a PH of 3.80. What is the concentration of the hydroxide ion in the juice? A. 1.6 \(\times\) 10-4 B. 6.3 \(\times\) 10-11 C. 6.3 \(\times\) 10-4 D. 1.6 \(\times\) 10-11 |
|
| 17. |
Incomplete oxidation of ethanol yields A. CH3COOH B. CH3COCH3 C. CH3CH2OCH2CH3 D. CH3CHO Detailed SolutionC2H5OH → CH3CHO → CH3COOHEthanol.....oxidation Ethanal........Ethanoic Acid Primary alcohol oxidises to aldehyde and later to carboxylic acid. Secondary alcohol oxidises to ketones. Ethanol is an example of primary alcohol and primary alcohol can be oxidised to aldehyde and carboxylic acid. Wherein, incomplete oxidation of primary alcohol yields aldehyde also known as alkanal while complete oxidation of primary alcohol yields carboxylic acid. There is an explanation video available below. |
|
| 18. |
The salt formed from a weak acid and a strong base hydrolyzes in water to form A. A saturated solution B. an acidic solution C. a buffer solution D. an alkaline solution |
|
| 19. |
The ideal gas laws and equations are true for all gases at A. low pressures and lower temperatures B. low temperatures and high pressures C. high pressures and high temperatures D. low pressure and high temperatures |
|
| 20. |
When ΔH is negative, a reaction is said to be A. endothermic B. exothermic C. reversible D. ionic |