In which of the following is the oxidation number of sulphur equal to -2?
- A. S8
- B. H2S
- C. SO 2
- D. SO 3 2-
What is the value of x in the following equation? Cr2O72- + 14H+ + xe- → 2Cr3+ + 7H2O
- A. 1
- B. 6
- C. 8
- D. 12
Which of the following will displace copper from a solution of copper (ll) salt?
- A. Aluminium ions
- B. Magnesium
- C. Silver
- D. Zinc ions
A finely divided form of a metal burns more readily in air than the rod form because the rod has
- A. higher molar mass
- B. smaller surface area
- C. protective oxide coating
- D. diferent chemical properties
What is the effect of using vanadium (V) oxide as catalyst in the reaction represented by the following equation? 2SO2 + O2 ⇌ 2SO3; ∆H = – xKJmol-1
- A. Decreases the value of ∆H
- B. Increases the collision rate of reactant particles
- C. Shifts equilibrium position to the right
- D. Reduces the time for attainment of equilibrium
Chemical equilibrium is attained when
- A. reactants in the system are used up
- B. concentrations of the products are greater than those of the reactants
- C. concentrations of the reactants and products remain constant
- D. reactants stop forming the products
What type of reaction is involved when wood shavings produce a brown gas with concentrated HNO3?
- A. Redox reaction
- B. Destructive distillation
- C. Dehydration
- D. Nutralization
Which of the following salts is an acid salt?
- A. MgSO 37H 2O
- B. (NH 4) 2CO
- C. KHSO4
- D. CH3COONa
Which of the following compounds dissolves in water to give an alkaline solution?
- A. Ammonium chloride
- B. Sodium chloride
- C. Sulphur (IV) oxide
- D. Potassium oxide
Which of the following salts is stable to heat?
- A. K2CO3
- B. (NH4)2SO4
- C. NaHCO 3
- D. AgNO3
If a solution has a pH of 2, it can be concluded that it
- A. is a weak electrolyte
- B. has hyrogen ion concentration of 0.2 mol dm-3
- C. is twice as acidic as a solution of pH 1,
- D. will produce effervescence with magnesium ribbon
The gas evolved when dilute tetraoxosulphate (VI) acid reacts with sodium hydrogen trioxocarbonate (IV) is
- A. hydrogen
- B. oxygen
- C. carbon (IV) oxide
- D. sulphur (VI) oxide
Which of the following gases is colourless, odourless and soluble in potassium hydroxide solution?
- A. NO 2
- B. SO 2
- C. NH 3
- D. CO2
9.60 g of a gas X occupies the same volume at 0.30 g of hydrogen under the same conditions. Calculate the molar mass of X [H = 1]
- A. 8g mol -1
- B. 16 gmol -1
- C. 32g mol -1
- D. 64g mol -1
Which of the following increases as boiling water changes to steam?
- A. temperature of the system
- B. degree of disorder in the system
- C. number of molecules
- D. activation energy
What are the values of x and y in the following equation? \(^{234}_{90}\)Th → \(^y_x\)Pa + ß- particle
- A. 91 234
- B. 92 235
- C. 89 235
- D. 88 238
What is the shape of a molecule of CCI4?
- A. Pyramidal
- B. Tetrahedral
- C. Trigonal planar
- D. Linear
A radioactive solid is best stored
- A. under paraffin oil
- B. under ultraviolet light
- C. in a cool, dark cupboard
- D. in a box lined with lead
Which of the following non-metals reacts most readily with metals?
- A. Nitrogen
- B. Chlorine
- C. Sulphur
- D. Carbon
Elactrostatic force of attraction between sodium ion and halide ion is greatest in
- A. NaCI
- B. NaBr
- C. NaF
- D. NaI
Which of the following contains co-ordinate covalent bond?
- A. HCI
- B. CH 4
- C. NH4
- D. Na+CI