In which of the following are the substances arranged in their correct order of increasing melting point?
- A. Sodium chloride, sulphur, diamond
- B. Diamond, sodium chloride, sulphur
- C. Sulphur, sodium chloride, diamond
- D. Diamond, sulphur, sodium chloride
- E. Sulphur, diamond, sodium chloride
Which of the following statements is not correct? Group 7 elements
- A. are diatomic
- B. are good oxidizing agents
- C. are highly electronegative
- D. have relatively low ionization potentials
- E. have high electron affinity
Which of the following modes of motion is exhibited by the particles of a solid?
- A. Vibrational and random motion
- B. Vibrational and translational motion
- C. Translational and random motion
- D. Vibrational motion only
- E. Translational motion only
The products of the electrolysis of dilute sodium chlorid solution with platinum electrodes are
- A. hydrogen and oxygen
- B. oxygen and chlorine
- C. chlorine and water
- D. sodium amalgam and chlorine
- E. sodium hydroxide and water
Which of the following formula is that of a dicarboxylic acid?
- A. (CH3CH 2)2CHCOOH
- B. CH2(OH)2
- C. CH3CH(OH)COOH
- D. CH2(COOH)2
- E. CH3COCOOH
Brass is an alloy of copper and
- A. iron
- B. chromium
- C. zinc
- D. tin
- E. magnesium
CH2 = CH2 + H2SO4 → CH3 – CH2 -OSO3H. The reaction illustrated by the equation above is an example of
- A. substitution
- B. oxidation
- C. reduction
- D. addition
- E. displacement
Which of the following elements can from more than one acidic oxide?
- A. Hydrogen
- B. Sulphur
- C. Carbon
- D. Alumium
- E. Iron
Which of the processes represented by the following equations has the greatest positive entropy change?
- A. C6H3(l) → C6H 6 (g)
- B. H2O (s) → H2O(l)
- C. CuO(s) + H2(g) → Cu(s) + H2
- D. Na2CO3(s) + nH2O(l) →Na 2CO3nH2O(s)
- E. S(s) → S(l)
What is the amount (in mole) of sodium trioxocarbonate (IV) in 5.3 g of the compound? (Na2CO3 = 106)
- A. 0.05
- B. 0.10
- C. 0.20
- D. 0.50
- E. 2.00
When air is passed through a heated tube containing finely divided copper, the component that is absorbed in the process is
- A. carbon (IV) oxide
- B. nitrogen
- C. oxygen
- D. water vapour
- E. noble gases
The separation of a mixture of calcium trioxocarbonate (lV) and sodium trioxocarbonate (IV) is most easily carried out by using the differences in their
- A. physical states
- B. melting points
- C. Rf. values
- D. solubility
- E. boiling points
In which of the following is the oxidation number of nitrogen zero?
- A. SO2 and NH3
- B. NaNO3
- C. HNO2
- D. NOI3
- E. N2
The metal extracted from cassiterite is
- A. calcium
- B. copper
- C. tin
- D. sodium
- E. lead
Petrol can be obtained from diesel by
- A. distillation
- B. cracking
- C. catalysis
- D. polymerization
- E. dehydrogenation
The following metals are extracted by the electrolytic method except
- A. potassium
- B. calcium
- C. sodium
- D. tin
- E. magnesium
Which of the following compounds crystallizes without water of crystallization?
- A. Na2CO3
- B. CuSO4
- C. MgSO4
- D. NaCI
- E. FeSO4
The decomposition of hydrogen peroxide is represented by the equation: 2H2O(l) + O2(g) what mass of hydrogen peroxide would be required to produce 22.4dm3 of oxygen at s.t.p? (H = 1, O = 16, molar volume of a gas at s.t.p. = 22.4dm3)
- A. 18 g
- B. 34 g
- C. 36 g
- D. 64 g
- E. 68 g
Nuclear reactions can be used in the following except
- A. gauging the thickness of objects
- B. making atomic bombs
- C. curing cancer
- D. generating electricity
- E. purifying water
Which of the following is normally used for drying ammonia gas?
- A. Concentrated tetraoxonitrate (Vl) acid
- B. Calcium oxide
- C. anhydrous calcium chloride
- D. phosphorus (V) oxide
- E. anhydrous copper (ll) tetraoxosulphate (VI)
Which of the following explains why trioxonitrate (V) acid is not used for preparing hydrogen from metals?
- A. it is volatile
- B. it is strongly oxidizing
- C. it forms a layer of oxide on the metal
- D. trioxonitrate (V) salts are soluble in water
- E. it renders the metals passive