NO(g) + CO(g) ↔ (1)/(2)N2(g) + CO2(g) ∆H = 89.3 kj.
What conditions would favour maximum conversion of nitrogen (II) oxide and carbon (II) oxide in the reaction above?
- A. Low temperature and high pressure
- B. High temperature and low pressure
- C. High temperature and high pressure
- D. Low temperature and low pressure
1.1 g of CaCI2 dissolved in 50 cm3 of water caused a rise in temperature of 3.4°C. The heat of reaction, ∆H for CaCI2 in kj per mole is?
(Ca = 40, CI = 35.5, specific heat of water is 4.18 jk-1)
- A. -71.1
- B. -4.18
- C. +71.1
- D. +111.0
Magnesium (IV) oxide is known to hasten the decomposition of hydrogen peroxide. Its main action is to?
- A. increase the surface area of the reactants
- B. increase the concntration of the reactants
- C. lower the activation energy for the reaction
- D. lower the heat of reaction, ∆H, for the reaction
2H2S(g) + SO2(g) → 3S(s) + 2H2O(I). The above reaction is?
- A. a redox reaction H2S is the oxidant and SO2 is the reductant
- B. a redox reaction in which SO2 is the oxidant and H2S is the reductant
- C. not a redox reaction because there is no oxidant in reaction equation
- D. not a redox because there is no reductant in the reaction equation
MnO–4 + 8H+ + ne → Mn++ + 4H2O. Which is the value of n in the reaction above?
- A. 2
- B. 3
- C. 4
- D. 5
Which of the following equimolar solutions, Na2CO3 Na2 SO
4CI FeCI3 CH3COONa,
have pH greater than 7?
- A. FeCI 3 and NH 4CI
- B. Na2CO3, CH3COONa and Na,Na2SO4
- C. Na2CO3 and CH3COONa
- D. FeCI3, CH3COONa and NH4CI
If a current of 1.5 A is passed for 4.00 hours through a molten tin salt and 13.3g of tin is deposited, what is the oxidation state of the metal in the salt?
(Sn = 118.7, F = 96500 C mol-1)
- A. 1
- B. 2
- C. 3
- D. 4
What volume of CO2 at s.t.p would be obtained by reacting trioxocarbonate (IV) with excess acid?
(G.M.V at s.t.p = 22.4 dm3)
- A. 2.240 cm 3
- B. 22.40 cm 3
- C. 224.0 cm 3
- D. 2240 cm 3
How many structural isomers can be written for the alkyl bromide, C4H9Br?
- A. 3
- B. 4
- C. 6
- D. 8
50 cm\(^3\) of sulphur (IV) oxide, 800cm\(^3\) of ammonia, 450 cm\(^3\) of hydrogen chloride, 1.0 cm\(^3\)of Carbon(IV) oxide will respectively saturate 1.0 cm\(^3\) of water at 15°C. Which of the following is suitable for demonstrating the fountain experiment?
- A. Sulphur (IV) oxide and hydrogen chloride
- B. Carbon (IV) oxide and ammonia
- C. Ammonia and hydrogen chloride
- D. Carbon (IV) oxide and surphur (IV) oxide
A property of a colloidal dispersion which a solution does not have is?
- A. the Tyndall effect
- B. homogeneity
- C. osmotic pressure
- D. surface polarity
A sample of temporary hard water can be prepared in the laboratory by?
- A. disolving calcium chloride in distilled water
- B. saturating lime water with carbon (IV) oxide
- C. saturating distilled water with calcium hydroxide
- D. dissolving sodium hydrogen trioxocarbonate (IV) in some distilled water
The solubility of copper (II) tetraoxosulphate (Iv) is 75g in 100g of water at 100°C and 25g in 100g of water at 30°C. What mass of the salt would crystallize, if 50g of copper (II) tetraoxosulphate (VI) solution saturated at 100°C were cooled to 30°C ?
- A. 57.5
- B. 42.2
- C. 28.6
- D. 14.3
Which of the following ions is a pollutant in drinking water even in trace amounts?
- A. Ca2+
- B. Hg2+
- C. Mg2+
- D. Fe2+
A quantity of air was passed through a weighed amount of alkaline pyrogallol. An increase in the weight of the pyrogallol would result from the absorption of?
- A. nitrogen
- B. neon
- C. argon
- D. oxygen
Which of the following is arranged in order of increasing electronegativity?
- A. Chlorine, aluminium, magnesium, phosphorus, sodium
- B. sodium, magnesium, aluminium, phosphorus, chlorine
- C. Chlorine, phosphorus, phosphorous, aluminium, magnesium, sodium
- D. Sodium, chlorine, phosphorus, magnesium, aluminium
Which of the following represents the type of bonding present in ammonium chloride molecule?
- A. Ionic only
- B. Covalent only
- C. Ionic and dative covalent
- D. Dative covalent only
The ions X– and Y+ are isoelectronic, each containing a total of 10 electrons.
How many protons are in the nuclei of the neutral atoms of X and Y respectively?
- A. 10 and 10
- B. 9 and 9
- C. 11 and 9
- D. 9 and 11
The electronic configuration of an elements is 1s22s22p63s23p3. How many unpaired electrons are there in the element?
- A. 5
- B. 4
- C. 3
- D. 2
Atoms of element X (with 2 electrons in the outer shell). combine with atoms of Y (with 7 electrons in the outer shell). Which of the following statements is FALSE? The compound formed?
- A. has formula XY
- B. is likely to be ionic
- C. contains X2+ ions
- D. contains Y- ions
A sample of a gas exerts a pressure of 8.2 atm when confined in a 2.93 dm3 container at 20°C. The number of moles of gas in the sample is?
(R = 0.082 litre atm / deg mole)
- A. 1.00
- B. 2.00
- C. 3.00
- D. 4.00