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The quick-lime is a drying agent that can dry most gases except ammonia. Hence it removes the water vapour. Quick-lime which is calcium oxide reacts with the carbon dioxide forming calcium carbonate. Hence carbon dioxide and monoxide is eliminated leaving nitrogen, and the rare gases

Oxygen is collected in downward displacement of water because:- Oxygen is only slightly soluble in water. Therefore, it can be collected over water without the fear of excessive dilution. Oxygen is slightly heavier than air, so it cannot be collected over air.

A catalyst is a substance that enables a chemical reaction to proceed at a usually faster rate or under different conditions (as at a lower temperature) than otherwise possible.

When we burn coal on a fire, the bonds break apart and the energy is released in the form of heat. Coal contains about half as much energy per kilogram as cleaner fossil fuels such as gasoline, diesel, and kerosene—and that's one reason why steam engines have to burn so much of it. Coal is the fuel used to power steam engines.

2NaOH + H\(_2\) SO\(_4\)↔Na\(_2\)SO\(_4\) + 2H\(_2\)O V x 0.5M = 2(10 x 1.25) 0.5V = 2 x 12.5 0.5V = 25 V = 250.5 = 50cm\(^2\) Correct computation as it follows the equation specified.

From the dilution law C\(_1\)V\(_1\) = C\(_2\)V\(_2\) C\(_1\) = Initial Concentration of NaOH = 0.6M V\(_1\) = Initial Volume of NaOH = 300cm3 C\(_2\) = Final Concentration of NaOH = 0.4M V\(_2\) = Final Volume of NaOH = ? V\(_2\) = \(\frac{C_1V_1}{C_2}\) V\(_2\) = \(\frac{0.6 \times 300}{0.4}\) V\(_2\) = 450 cm\(^3\) Correct Computation as it follows the equation specified

Diamond is a covalent macromolecule, and typical of a covalent substance is an insulator. All valence electrons are localized in well-defined covalent bonds and hence are not free to move through the structure

Esterification is a chemical reaction that forms at least one ester (= a type of compound produced by reaction between acids and alcohols). Esters are produced when acids are heated with alcohols in a process called esterification. An ester can be made by an esterification reaction of a carboxylic acid and an alcohol.

Constituents of duralumin are: Al, Cu, Mg, Mn. Constituents of Alnico are: Al, Ni and Co In 1909, the alloy of duralumin was discovered by Alfred Wilon consisting of 94% Al, 4% Cu, 1% Mg and 1% Mn(Manganese) Alnico is an acronym referring to a family of iron alloys which in addition to iron are composed primarily of Al, Ni and Co.

increasing temperature in exothermic reaction favors the left/reactant side and decreasing temperature will favor the right/product side.

M = \(\frac{MmIT}{96500n}\) Where M=mass Mm = Molar mass = 64g/mol I = current = 1.6A T= Time =1h r=3600s N= No of Charge = +2 M = \(\frac{64x \times 1.6 \times 3600}{96500 \times 2}\) M=1.91g

Recall from pH formula pH = -Log [H+] H2SO4 → 2H+ + SO42- 2H+ → 2 X0.05 = 0.1 pH= -Log [0.1] = 1

The method used to extract a metal from its ore depends upon the stability of its compound in the ore, which in turn depends upon the reactivity of the metal: • The oxides of very reactive metals, such as aluminum, form stable oxides and other compounds. A lot of energy is needed to reduce them to extract the metal. • The oxides of lesser reactive metals, such as iron, form less stable oxides and other compounds. Relatively little energy is needed to reduce them to extract the metal. So, the method of extraction of a metal from its ore depends on the metal's position in the reactivity series.

Aluminium hydroxide is not soluble in water because it is polymeric and it also has high lattice energy and therefore it is hard to break bonds in this compound. So, water cannot dissolve such types of compounds. Al(OH)\(_3\) is not soluble in water