Chemistry Past Questions And Answers
The highest level of molecular disorderliness is found in
- A) ice at -10°C
- B) water at 100°C
- C) steam at 100°C
- D) ice at 0°C
The formation of ozone by reaction of O2 with atomic oxygen in UV light occurs in
- A) upper atmosphere
- B) inner atmosphere
- C) stratosphere
- D) hemisphere
What is the value of -14°C on the Kelvin temperature scale?
- A. 259K
- B. 287K
- C. 287°K
- D. 259°K
Liquid black soap is made by boiling palm oil with liquid extract of ash. The function of the ash is to provide the ?
- A. Acid
- B. Ester of alkanoic acid
- C. Alkali
- D. Alkanol
Calculate the quantity of electricity in coulombs required to liberate 10g of copper from a copper compound[Cu=64, F = 96500 Cmol-1]
- A) 32395.5
- B) 30156.3
- C) 60784.5
- D) 15196.5
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
The molecular formula of a common organic laboratory anaesthetic is
- A) CHCl3
- B) CHI3
- C) CCl4
- D) CHF3
Neutral atoms of neon with atomic number 10 have the same number of electron as
- A. O2+
- B. Ca2+
- C. K+
- D. Mg2+
Hydrogen is used in oxy-hydrogen flames for melting metals because it
- A. evolves a lot of heat when burnt
- B. combines explosively with oxygen
- C. is a very light gas
- D. is a rocket fuel
The number of isomers that can be obtained from C4H10 is
- A) 3
- B) 4
- C) 1
- D) 2