Calculate the mass of copper deposited if a current of 0.45A flows through \(CuSO_{4}\) solution for 1hour 15mins. [Cu=64.0, S= 32.0, O =16.0, 1F= 96500C]
- A. 6.40g
- B. 0.67g
- C. 0.64g
- D. 0.45g
Which of the following factors characterize members of the same homologous series?
- A. The chemical property change gradually throughout the series
- B. physical properties of members are similar
- C. They have the same molecular formular
- D. Successive members undergo changes in molecular formula by \(CH_{2}\)
Consider the following reaction equation: \(2NO_{(g)} + O_{{2}{(g)}} \to 2NO_{{2}{(g)}}\). What is the change in the oxidation number of nitrogen?
- A. +2 to 0
- B. +2 to -2
- C. +2 to +4
- D. +4 to +2
The common feature of reactions at the anode is that
- A. electrons are consumed
- B. ions are reduced
- C. oxidation is involved
- D. the electrode dissolves
Chemical reactions occurs when the colliding reactants have energy that is
- A. less than the activation energy
- B. greater than the activation energy
- C. greater than the energy of the product
- D. less than the energy of effective collision
Soluble salts can be prepared by the following methods except
- A. neutralization
- B. reaction of an acid with trioxocarbonate(IV) salt
- C. double decomposition
- D. reaction of an acid with electropositive metals
The property of a chemical reaction that is affected by the presence of a catalyst is
- A. activation energy
- B. free energy
- C. equilibrium position
- D. enthalpy change
If 0.2g of a salt is required to saturate 200\(cm^{3}\) of water at room temperature, what is the solubility of the salt?
- A. 0.2\(gdm^{-3}\)
- B. 1.0\(gdm^{-3}\)
- C. 2.0\(gdm^{-3}\)
- D. 5.0\(gdm^{-3}\)
Solubility curve can be used in the determination of the
- A. amount of crystals formed
- B. amount of solvent that can be recovered
- C. amount of solid drugs in a given solution
- D. temperature of the solution
When water was added to a white anhydrous substance X, the colour changed to blue. X is
- A. \(CuSO_{4}\)
- B. \(FeSO_{4}\)
- C. \(Na_{2}SO_{4}\)
- D. \(PbSO_{4}\)
Potassium Chloride solid does not conduct electricity because
- A. it is a covalent compound
- B. strong cohesive forces make its ions immobile
- C. strong cohesive force makes its molecule immobile
- D. each of potassium and chlorine structures contain noble gas structure
Halogens generally react with metals to form
- A. alkalis
- B. acids
- C. bases
- D. salts
Which of the following statements is NOT a chemical property of an acid?
- A. Evolution of ammonia when heated with ammonium salts
- B. Evolution of carbon dioxide gas when added to a trioxocarbonate (IV) salt
- C. Formation of salt and water with alkalis
- D. Formation of salt and hydrogen gas with reactive metals
A hydrocarbon contained 14.3% hydrogen. The empirical formula for the hydrocarbon is [H= 1.0, C= 12.0]
- A. \(CH\)
- B. \(CH_{2}\)
- C. \(CH_{3}\)
- D. \(CH_{4}\)
Which of the following gases is not acidic?
- A. \(SO_{3}\)
- B. \(NO_{2}\)
- C. \(Co_{2}\)
- D. CO
When Magnesium reacts with oxygen, heat is
- A. absorbed and the reaction is endothermic
- B. evolved and the reaction is endothermic
- C. evolved and the reaction is exothermic
- D. absorbed and the reaction is exothermic
The number of atoms present in 2.5moles of a triatomic gas is equivalent to [1mole = \(6.02\times 10^{23}\)]
- A. \(2.5\times 10^{23}\)
- B. \(1.5\times 10^{23}\)
- C. \(1.5\times 10^{24}\)
- D. \(2.5\times 10^{24}\)
In a saturated solution at a given temperature, the undissolved solutes are in equilibrium with
- A. the solvent
- B. dissolved solute particles
- C. the saturated solution
- D. insoluble solute particles
Graphite and Diamond are similar in that they
- A. have octahedral shape
- B. have same density
- C. form carbon(IV) oxide on combustion
- D. conduct electricity
A 0.1\(moldm^{-3}\) solution of sodium hydroxide was diluted with distilled water to 0.001\(moldm^{-3}\). What is the dilution factor?
- A. 1000.00
- B. 100.00
- C. 10.00
- D. 0.01
Which of the following statements about endothermic reaction is correct?
- A. Activation energy is high
- B. A catalyst is required
- C. It occurs reversibly
- D. Heat energy is absorbed