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Chemistry Questions

Question 296:

Which of the following combinations of conditions may increase the rate of a chemical reaction?

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A Decrease in temperature, increase in concentration of the reactants
B Increase in temperature, addition of a catalyst, decrease in the surface area of the reactants
C Increase in temperature, increase in concentration, addition of a catalyst and increase in the surface area of the reactants
D Decrease in temperature concentration and surface area of the reactants
E Additionof a catalyst and in the absence of light

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Question 297:

Which of the following is NOT a redox reaction?

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A 2HNO<sub style='font-size: smaller;'>2</sub> + 2HI â†’ 2H<sub style='font-size: smaller;'>2</sub>O + 2NO + I<sub style='font-size: smaller;'>2</sub>
B Zn + H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub> → ZnSO<sub style='font-size: smaller;'>4</sub> + H<sub style='font-size: smaller;'>2</sub>
C Ca(HCO<sub style='font-size: smaller;'>3</sub>)<sub style='font-size: smaller;'>2</sub> â†’ CaCO<sub style='font-size: smaller;'>3</sub> + H<sub style='font-size: smaller;'>2</sub>O + CO<sub style='font-size: smaller;'>2</sub>
D 4FeO + O<sub style='font-size: smaller;'>2</sub> â†’ 2Fe<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>3</sub>
E 2Na + Cl<sub style='font-size: smaller;'>2</sub> â†’ 2NaCl

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Question 298:

0.16g of methane when burnt raises the temperature of 100g of water by 40°C. What is the of combustion of methane when if the heat capacity of water is 4.2 Jg<sup style='font-size: smaller;'>-1</sup>°C<sup style='font-size: smaller;'>-1</sup>?<br/>(CH<sub style='font-size: smaller;'>4</sub> = 16)

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A 1,160 kJ mol<sup style='font-size: smaller;'>-1</sup>
B 1,180 kJ mol<sup style='font-size: smaller;'>-1</sup>
C 1,560 kJ mol<sup style='font-size: smaller;'>-1</sup>
D 1,600kJ mol<sup style='font-size: smaller;'>-1</sup>
E 1,680 kJ mol<sup style='font-size: smaller;'>-1</sup>

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Question 299:

Which of the following processes NOT lead to a chemical change?

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A Strirring iron in sulphur (IV) acid
B Stirring sodium carbonate in water
C Stirring glucose in concentrated sulphur (IV) acid
D Mixing sulphur (IV) acid with potassium carbonate
E Titrating an acid against base

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Question 300:

Brass is an alloy containing copper and?

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A Zinc
B Tin
C Aluminium
D Silver
E Lead

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