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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

When we ignite a candle, the hydrocarbon reacts with oxygen (in excess) to produce carbon dioxide and water. The burning sets an air current which gives dome shape to candle flame and it helps to get complete combustion at the bottom and the outer surface of the flame. CO\(_2\) is produced

Collision theory is the theory used to predict the rates of chemical reactions, particularly for gases. The collision theory is based on the assumption that for a reaction to occur it is necessary for the reacting species (atoms or molecules) to come together or collide with one another.

Ammonia gas can be removed from a dessicator by adding a conc. H2SO4 so as to neutralize it since ammonia gas is basic.

Aluminium doesn’t react with either dilute or concentrated trioxonitrate (V) acid because an insoluble oxide is formed on its surface which renders it passive. It will depend on the concentration of the nitric acid used…. Although aluminium reacts with dilute nitric acid to produce aluminium nitrate and hydrogen gas, concentrated (>60%) nitric acid is such a powerful oxidising agent that it instantly causes a thin layer of aluminium oxide to coat the surface of the aluminium

During the electrolysis of brine, the chlorine ions are discharged at the anode and are oxidized. While at the cathode Hydrogen ion is discharged.

Half-life, in radioactivity, the interval of time required for one-half of the atomic nuclei of a radioactive sample to decay (change spontaneously into other nuclear species by emitting particles and energy), or, equivalently, the time interval required for the number of disintegrations per second of a radioactive material to decrease by one-half