0.07g of a hydride of carbon occupies 56.0cm3 at S.T.P. when vaporized and contains 14.29% by mass of hydrocarbon is(C = 12, H = 1)
- A. CH4
- B. C2H2
- C. C2H4
- D. C2H6
- E. C3H8
A mixture contains 20cm3 of hydrogen, 35cm3 of oxygen, 15cm3 of carbon monoxide and 10cm3 of nitrogen at S.T.P. Which of the following gives the mole fraction of hydrogen in this mixture?
- A. 0.02
- B. 0.16
- C. 0.20
- D. 0.25
- E. 20
100 cm3 of oxygen is made to react with 50 cm 3 of hydrogen, and the whole reaction mixture was then passed through anhydrous calcium chloride. What is the volume of gas left?
- A. 5 cm3
- B. 25 cm3
- C. 50 cm3
- D. 75 cm3
- E. 100 cm3
9.8g of solid potassium chlorate (KCIO3) were added to 40 cm3 of water and heated to dissolve all the solid. As he solution cooled, crystals of potassium chlorate started forming at 60°C. The solubility of potassium chlorate at 66°C is therefore?
- A. 24.5 mole per dm3
- B. 0.2 mole per dm3
- C. 10.0 mole per dm3
- D. 20.0 mole per dm3
- E. 2.0 mole per dm3
When air is passed through alkaline pyrogallol and then over quicklime, the only gases left are?
- A. nitrogen and carbondoxide
- B. the rare gases
- C. nitrogen and oxygen
- D. nitrogen and the rare gases
- E. nitrogen, carbonioxide and the rare gases
The nitrogen gas obtained by burning an excess of phosphorus in air has a density higher than the nitrogen from nitrogen compounds because the nitrogen from air is contaminated with?
- A. some unburnt phosporus
- B. P2O5 vapour
- C. some oxygen
- D. rare gases
- E. carbondioxide
If atom X with six electrons in its outermost shell combines with atom Y with one electron in its outermost shell to form an ionic compound, then?
- A. six atoms of X will combine with one of Y
- B. two atoms of X will combine with six of Y
- C. one atom of X will combine with two of Y
- D. two atoms of X will combine with one of Y
- E. one atom of X will combine with six of Y
When a little brine was added to a metal nitrate a white precipitate was formed which first turned violet and then black on exposure to ai. The metal nitrate is therefore?
- A. sodium nitrate
- B. mercuric nitrate
- C. lithium nitrate
- D. silver nitrate
- E. potassium nitrate
If the temperature of a gas is increased?
- A. the kinetic energy of the emolecules will decrease
- B. the pressure will decrease if the volume is constant
- C. the gas will occupy a greater volume if the pressure is constant
- D. the mass of the gas will decrease
- E. the pressure and volume will increase
If the rate of diffusion of oxygen gas is taken as 1, what will be rated of diffusion of methane whose relative molar mass is 16?
- A. 2.0
- B. 1.8
- C. 1.4
- D. 1.0
- E. 0.5
Which of the following equations represents an oxidizing action of sulphur dioxide?
- A. SO2 + 2HNO2 → H2SO4 + 2NO2 + heat
- B. 2SO2 + 2H2O + O2 → 2H2SO4
- C. SO2 + 2H2O + CI2 → H2SO4 + 2HCI
- D. SO2 + 2H2S → 3S + 2H2O
- E. K2Cr2O7 + H2SO4 + 3SO2 → K2SO4 + Cr2(SO4)3 + H2O
Which of the following represents ethyl ethanonate?
- A. CH3CH2CO2CH3
- B. (CH3CO2)2O
- C. CH3CH2CO2CH2CH3
- D. CH3CO2CH2CH3
- E. CH3CH2COCH2CH3
The production of ammonia by the haber process may be represented by the equilibrium equation N2(g) + 3H2(g) ↔ 2NH3 ∆H = -22KJ. Therefore the production of ammonia will be favoured by?
- A. only high pressure
- B. only high temperature
- C. a combination of high temperature and low pressure
- D. a combination of low temperature and high pressure
- E. low pressure
When a solution of silver (l) nitrate is saturated with hydrogen sulphide, a black precipitate forms which is?
- A. H2S
- B. Ag2S
- C. PbS
- D. HNO3
- E. S
1.00 g of the oxide of metal X (atomic mass = 64) gave 0.80 g of the metal when reduced with hydrogen.
The formula of the oxide is?
- A. X2O
- B. XO
- C. XO2
- D. X2O3
- E. X3O4
In the chemical reaction A + B \(\to\) C + D, more of D is formed?
- A. if the concentrated of A is reduced
- B. if the concentrated of B is reduced
- C. if the concentrated of C is reduced
- D. if the concentration of C is increased
- E. if D is continuously removed from the reaction mixture
In the reaction N2(g) + O(g)
↔ 2NO(g) produced i an increase in the total pressure will?
- A. cause less nitrogen to be produced in the equilibrium mixture
- B. cause less nitric oxide to be produced in the equilibrium mixture
- C. cause more nitric oxide to be produced in the equilibrium mixture
- D. cause more oxygen to be produced in the equilibrium mixture
- E. have no effect
Which of the following CANNOT be obtained by fractional distillation of petroleum?
- A. Ether
- B. Methane
- C. Butane
- D. Ethene
- E. Hydrogen
In the reaction NH3 + H+ → NH4+, the bond formed results from?
- A. an electron transferred from NH3 + H+
- B. an electron pair donated by NH3
- C. an electron pair equally shared
- D. an electron pair donated by H+
- E. an electron tarnsferred from H+ to NH3
Which of the following statements is incorrect?
- A. Calcium reacts with water to form calcium
- B. Magnesium reacts very slowly with water but faster with warm water
- C. Iron will not react with water in the absence of air
- D. Sodium reacts with water
- E. Copper reacts with steam
Sodium carbonate crystals on exposure to a dry atmosphere change to a white powder. This phenomenon is known as?
- A. deliquescence
- B. hygroscopy
- C. oxidation
- D. efforescence
- E. sublimation