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Benzene reacts with a mixture of concentrated nitric acid and concentrated sulphuric acid to form nitrobenzene at a temperature not exceeding 60^\circC. The reaction is known as the nitration of benzene.

The general molecular formula C\(_n\)H\(_{2n-2}\) represents that of an alkyne with its first member as ethyne

Covalent molecules have low melting and boiling points because of their weak intermolecular forces.The force of attraction between the molecules in a covalent compound is weak, so it takes little energy to break the bonds. Yes, all covalent compounds have a three-dimensional structure due to the directional nature of covalent bonds, which means the atoms within a molecule are arranged in a specific spatial orientation, giving the molecule a definite shape in three dimensions; this is explained by the Valence Shell Electron Pair Repulsion (VSEPR) theory.

When an alcohol is oxidized in a warm solution of potassium dichromate (VI) and dilute sulphuric acid, the solution changes colour from orange to green. This is because the Cr\(_2\)O\(_7\)\(^{2-}\) ions in the solution are reduced to Cr\(^{3+}\) ions. This colour change can be used to identify alcohols. Only alcohols will cause the solution to change colour from orange to green.

Hydrochloric acid is not suitable for preparing ethanoic acid because it is too volatile.Being too volatile, means it has a low boiling point and is easily evaporated. Thus, HCl is not suitable because it cannot carry out the oxidation process required to convert alcohols into acids like ethanoic acid. Ethanoic acid, also known as acetic acid, is a weak acid that doesn't fully dissociate in water, while hydrochloric acid is a strong acid that dissociates almost completely.

\(\frac{Original mass}{2^n}\) = Residual mass Where n = number of activity = \(\frac{exposure time}{half life}\) Given: Original mass = 1g, exposure time = 10 minutes , half life = 2 minutes, Residual mass = ? Substituting all the given parameters appropriately, we have n = \(\frac{10}{2}\) n = 5 \(\frac{Original mass}{2^n}\) = Residual mass \(\frac{1}{2^5}\) = Residual mass \(\frac{1}{32}\) = Residual mass Residual mass = \(\frac{1}{32}\) or 0.03125g

The fountain experiment demonstrates the solubility of gases in water. Hydrogen chloride gas and ammonia gas are used in the fountain experiment because they are both highly soluble in water. Hydrogen chloride: A liquid gas that is highly soluble in water and has an acidic nature. The acidic nature of hydrogen chloride is demonstrated in the fountain experiment when the blue litmus solution turns red. Also, Ammonia: A colourless gas with a pungent smell that is lighter than air

The current carriers in an aqueous copper sulphate (CuSO\(_4\)) solution are ions. When copper sulphate is dissolved in water, it dissociates into ions that can carry an electric charge. These ions are the current carriers in the solution. When dissolved in water as part of CuSO\(_4\), "Cu\(^{2+}\)" is considered a hydrated ion because it is surrounded by water molecules in solution, forming a complex ion like [Cu(H\(_2\)O)\(_6\)]\(^{2+}\). "Cu\(^{2+}\)" itself represents the copper metal ion, which is considered a metallic ion, but when in aqueous solution, it readily forms bonds with water molecules, becoming a hydrated ion. This means the copper ion is not simply "Cu2+" but is surrounded by water molecules, forming a complex ion like [Cu(H\(_2\)O)\(_6\)]\(^{2+}\)..

ClCH=CHCl can exhibit geometrical isomerism and positional isomerism. ClCH=CHCl can exhibit positional isomerism because the positions of the functional groups or substituent atoms are different. Positional isomerism occurs when compounds with the same molecular formula have different properties due to the difference in the position of a functional group, multiple bond, or branched chain.

The basicity of tetraoxophosphate(V) acid, or H\(_3\)PO\(_4\), is 3, making it a tribasic acid.

In the extraction of iron, "slag" refers to a molten, glassy by-product that forms on the surface of the molten iron during the smelting process, primarily composed of impurities like silicon dioxide (from the ore) that react with a flux (like limestone) added to the furnace, effectively separating these impurities from the pure iron and allowing them to be removed as a separate layer; essentially, it's a waste product created to remove unwanted materials from the iron ore during extraction. Slag is mainly a mixture of metal oxides and silicon dioxide. Limestone, CaCO\(_3\) is used to form slag in the blast furnace process during the extraction of iron. The limestone decomposes in the furnace to form calcium oxide (CaO), which then reacts with impurities like silicon dioxide, SiO\(_2\) to form calcium silicate, Ca\(_2\)SiO\(_4\)

NB: 1F = 1 mole of electrons of the atom of an element In the case of copper (Cu), the valency is 2+. ⇒ Cu\(^{2+}\) + 2e\(^-\) → Cu So, 2F = 1 mole of Cu then, 2F = x mole x = \(\frac{2\times1}{2}\) x = 1 mole

According to the Ideal gas equation, PV = nRT Given: P = 1.58 atm, V = ?, n = 1 mole, R = 0.082, T= 13 + 273K = 286K Substituting all the given parameters, V = \(\frac{nRT}{P}\) V = \(\frac{1\times0.082\times286}{1.58}\) V = 14.84 dm\(^3\)

If a salt weighs 2g and upon exposure to the atmosphere weighs 1.5g, it simply means it has lost some moisture content from it. This process is called efflorescence. Efflorescence is the process by which a hydrated salt loses water spontaneously when the aqueous vapour pressure of the hydrate is greater than the partial pressure of water vapour in the air. This causes the salt to lose all or part of its water of hydration, resulting in a powdery appearance on its surface.

CuCO\(_3\), is primarily used as a pigment in paints, ceramics, and fireworks due to its distinctive green colour, and is also utilized in agriculture as a fungicide and pesticide, as well as in some industrial applications like wood preservation and catalyst production; essentially, its main uses are as a colourant and in various chemical reactions as a precursor to other copper compounds. Cu({NO\(_3\)})2, also known as copper(II) nitrate, is primarily used as a source of copper ions in various applications, including: catalysis in organic chemistry, electroplating, textile dyeing, ceramic glazes, pyrotechnics, analytical chemistry, and as a component in some metal patinas; CuSO\(_4\), also known as copper sulphate, is primarily used as a fungicide and algaecide in agriculture, controlling unwanted fungi and algae on crops, as well as in water systems like ponds and aquariums; it can also be used as a pesticide to kill snails and slugs, and in some cases as a soil additive to correct copper deficiencies in the soil. CuCl\(_2\), also known as Copper(II) chloride, is primarily used as a catalyst in chemical reactions, including applications in the textile industry as a mordant, in the petroleum industry as a deodorizer and purifying agent, as a wood preservative, and in photography as a fixer;