Which of the following oxides of nitrogen is unstable in air?
- A. NO2
- B. NO
- C. N2O4
- D. N2O5-
Which of the following combination of gases is used for metal welding? i. Oxygen and ethyne, ii. Hydrogen and ethyne, iii. Hydrogen and oxygen, iv. Ethyne, hydrogen and oxygen.
- A. i and ii
- B. ii and iv
- C. i and iii
- D. ii and iv
Which of these statements is TRUE about carbon (IV) oxide?
- A. it supports combustion
- B. It is strongly acidic in water
- C. It is very soluble in water
- D. It supports the buring of magnesium to produce magnesium oxide
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. (p)x (Q)y / (R)m (S)n
- C. (R)m (S)n / (p)x (Q)y
- D. m(R) n (S) / x(P) y (Q)
Which of the following equilibria shows little or no net reaction when the volume of the system is decreased?
- A. H2(g) + I2(g) ≈ 2HI(g)
- B. 2NO2(g) ≈ N2O4(g)O4(g)N2O4(g)
- C. PCI5(g) ≈ PCI3(g) + CI2(g)
- D. ZnO(s) + CO2(g) ≈ ZnCO3(g)
In what way is equilibrium constant for the forward reaction related to that of the reversed reaction?
- A. The additional of the two is expected to be one
- B. The product of the two is expected to be one
- C. The two equilibrium constants are identical
- D. The product of the two is always greater than one
In which of the following is the entropy change positive?
- A. H2O(I) → H2O(g)
- B. Cu2+(aq) + Fe(s) → Fe(2+) + Cu(s)
- C. N2(g) + 3H2(g) → 2NH3(g)
- D. 2HCI(s) → H2(g) + CI2(g)
\(MnO_2 + 2CI^- + 4H^+ → Mn^{2+} + CI_2 + 2H_2O\).
The changes in oxidation numbers when the manganese, chloride, and hydrogen ions react according to the above equation are respectively?
- A. 2, 2, 4
- B. -1, -2, 4
- C. -2, 1, 0
- D. 2, 4, 0
S2O2-3 + I2 → S2O62- + 2I–. In reaction above, the oxidizing agent is?
- A. S2O32-
- B. I2
- C. S4O62-
- D. I-
Calculate the mass, in kilograms, of magnesium produced by the electrolysis of magnesium (II) chloride in a cell operating for 24 hours at 500 amperes.
- A. 2.7
- B. 5.4
- C. 10.8
- D. 21.7
Copper (II) tetraoxosulphate (VI) solution is electrolyzed using carbon electrodes. Which of the following are produced at the anode and cathode respectively ?
- A. Copper and oxygen
- B. Oxygen and copper
- C. Hydrogen and copper
- D. Copper and hydrogen
How many grams of H2SO4 are necessary for the preparation of 0.175 dm3 of M 6.00 M H2SO4?
(S = 32.06, O = 16.00 H = 1.00)
- A. 206.0 g
- B. 103.0 g
- C. 98.1 g
- D. 51.5 g
Arrange HCI, CH3COOH, C6H5CH3 in order of increasing conductivity.
- A. HCI, CH3COOH, C6H5CH3
- B. C6H5CH3, HCI, CH3COOH
- C. C6H5CH3, CH3COOH, HCI
- D. CH3COOH, C6H5CH3, HCI
A sample of orange juice is found to have a pH of 3.80. What is he concentration of the hydroxide ion in the juice?
- A. 1.6 x 10-4
- B. 6.3 x 10-11
- C. 6.3 x 10-4
- D. 1.6 x 10-11
An emulsion paint consists of ?
- A. gas or liquid particles dispersed in liguid
- B. liquid particles dispersed in liquid
- C. solid particles dispersed in liquid
- D. solid particles dispersed in solid
On which of the following is the solubility of a gaseous substance dependent? I. Nature of solvent II. Nature of solute III. Temperature IV. Pressure
- A. I, II, III and IV
- B. I and II only
- C. II only
- D. I, III and IV only
Water for town supply is chlorinated to make it free from?
- A. bad odour
- B. bacteria
- C. temporary hardness
- D. permanent hardness
Which of the following gases dissolves in water vapour to produce acid rain during rainfall?
- A. Oxygen
- B. Carbon (II) oxide
- C. Nitrogen
- D. Sulphur (IV) oxide
Four elements P,Q,R and S have 1,2,3, and 7 electrons in their outermost shells respectively. The element which is unlikely to be a metal is?
- A. P
- B. Q
- C. R
- D. S
The pollutants that are likely to be present in an industrial environment are?
- A. H2S,SO2 and oxides of nitrogen
- B. NH3, HCI and CO
- C. CO2, NH3 and H2S
- D. dust, NO and CI2
147N + X → 178O + 11 H. In the above reaction, X is a?
- A. neutron
- B. helium atom
- C. litgium atom
- D. deuterium atom