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Deposition is a thermodynamic process that occurs when a substance changes from a gas to a solid without passing through the liquid phase. This happens due to a decrease in temperature.The entropy change for the transition from gas to solid is negative because solids have lower entropy compared to gases, gas particles are more disordered and have a higher rate of motion compared to solids that have closely packed particles.

Microorganisms, such as yeasts, molds, and bacteria, break down organic substances, usually in the absence of oxygen. This process breaks down starch or cellulose chains into individual sugar molecules, which are then fermented into ethanol and carbon dioxide.

ROH - Alkanols R\(_2\)CO - Ketones RCOOR\(^1\) - Esters or alkanoates The general formula for alkanals is C\(_n\)H\(_{2n+1}\)CHO, where n = 0, 1, 2, 3, and so on. In other words, it is RCHO Alkanals are compounds that are formed when long-chain primary alcohols are oxidized. Primary alkylsulphates biodegrade to produce these alcohols.

Iron ore is typically found with various impurities, with the main impurity being silicon dioxide (SiO\(_2\)). To remove silicon dioxide from iron ore, calcium oxide (CaO) is added to the blast furnace. This is a neutralization reaction because silicon dioxide is acidic and calcium oxide is basic. CaO\(_{(s)}\) + (SiO\(_2\))\(_{(s)}\) → CaSiO\(_2\)\(_{(s)}\). Base Acid

Sulphur is added to rubber during vulcanization to create strong chemical bonds that improve the rubber's durability, strength, and elasticity. In other words it binds the molecules of rubber together

Hydrogenation of benzene involves the addition of 3 molecules of H\(_2\) = 6 Hydrogen atoms in all. To do this, the three double bonds present in the Benzene (C\(_6\)H\(_6\)) will be opened so that the 6 Hydrogen molecules can attach to the Carbon atoms each, resulting into C\(_6\)H\(_{12}\) (in a cyclic form, hence the name cyclo). Recall, Saturated Hydrocarbon with 6C atoms is called Hexane, hence the name is cyclohexane.

A trihydric alkanol is an alkanol with three hydroxyl (OH) groups. Glycerol is an example of a trihydric alkanol. Trihydric alkanol (e.g propan-1,2,3- triol, also known as glycerol) has three -OH group attached to the three C atoms. See diagram above

When chlorine is passed into water and the resulting solution is exposed to sunlight, the products formed are hydrochloric acid and oxygen gas. Firstly, Chlorine reacts with water to form hypochlorous acid. Cl\(_2\) + H\(_2\)O → HClO Secondly, hypochlorous acid breaks down into Hydrochloric acid and Oxygen gas. 2HClO → 2HCl + O\(_2\) Ultraviolet light from the sun provides the energy needed to break the chlorine molecule and starts the reaction.

Proteins can undergo a hydrolysis reaction when treated with a concentrated acid solution at a high temperature. This reaction breaks the peptide bonds that hold amino acids together, releasing the amino acids.

Polymerization of alkenes is a chemical reaction that combines small molecules called monomers into large molecules called polymers. This process occurs when the double bonds of alkene molecules break, and new single bonds form between the carbon atoms of adjacent monomer. Decarboxylation is a chemical reaction that removes a carboxyl group and releases carbon dioxide (CO\(_2\)). It usually refers to the removal of a carbon atom from a carbon chain in carboxylic acids.

Isomers refer to compounds that have the same molecular formula but are structurally different. Both But-1-ene and But-2-ene have the same number of Carbons and the same number of Hydrogen. The only difference is the positions of the double bond. Therefore, they are isomers

A candle is an hydrocarbon. Generally when hydrocarbons undergo combustion (like a burning candle), there are ususally two products yielded, which are water and carbon (iv)oxide. The answer is option B

The method used to collect a gas depends on whether it is denser or lighter than air. For example, ammonia gas is collected by downward displacement of air because it is lighter than air. Option C is the correct answer. Chlorine is heavier than air. SO\(_2\) is denser than air. CO\(_2\) is denser than air.

When heated, lead (Pb) burns with a bluish-white or greyish-white flame. When heated, calcium burns with a brick red flame and forms a white solid. The calcium ion (Ca2+) produces a brick red color in a flame test. When heated in air, sodium (Na) burns with a bright, golden yellow flame. When heated, magnesium burns with a bright, dazzling white flame.

Hybridization is the process of mixing orbitals with slightly different energies to create new orbitals with the same shape and energy. In ethyne, each carbon atom's 2s orbital combines with one of its 2p orbitals to form two sp hybrid orbitals. Ethyne, also known as acetylene, has sp hybridization