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Ethene = 28 Ethyne = 26 Carbon(ii)Oxide = 28 Carbon(iv)Oxide = 44

The term saturated solution is defined in chemistry as a solution in which no more solute can be dissolved in the solvent.

1 Mole of carbon(iv)oxide contains 32g of Oxygen : 0.5 Mole of carbon(iv)oxide contains 16g of Oxygen

The principles of stoichiometry are based upon the law of conservation of mass. Matter can neither be created nor destroyed, so the mass of every element present in the product(s) of a chemical reaction must be equal to the mass of each and every element present in the reactant(s).

- molecular mass (or molar mass) is 60.05 g/mol - with 4 atoms of hydrogen present ( 4 / 60 ) X 100 ≈6.7%

Aluminum chloride (Al2Cl6) has coordinate dative bonding In the solid state, aluminum chloride forms a dimer (Al₂Cl₆) where two aluminum atoms are connected by coordinate covalent bonds with chlorine atoms, stabilizing the structure.

- The longest chain has five carbon atoms i.e PENT - with two methyl attached to the second carbon atom

(mass / molar mass) X (1000 / vol ) (0.28 / 56.0) X (1000 / 100 ) = 2.8 / 56 = 0.05 mol\dm\(^3\)

Vinegar is an aqueous solution of acetic acid and trace compounds that may include flavorings.

Low PH means strongly acidic cause acidity increases with decreasing PH values. Example is Hydrochloric Acid

An acid gas is any gaseous compound which, when dissolved in water, will form an acidic solution The most common acid gases are hydrogen sulfide (H2S) and carbon dioxide (CO2) gases

Phenolphthalein is suitable as indicator for this reaction i.e strong base and weak acid

In other terms, the stronger the acid the greater the amount of hydrogen ions present in the solution, and hence the more alkali that should be required to neutralise the solution, hence increasing the enthalpy

- When quicklime is added to water, it forms slaked lime along with the evolution of heat. There will be a rise in the temperature of the bucket. Calcium oxide reacts with water to form calcium hydroxide, also called slaked lime. - That is adding water to quicklime produces an exothermic reaction (gives out heat) and hydrated lime.

- Endothermic reactions are chemical reactions in which the reactants absorb heat energy from the surroundings to form products. - A system of reactants that absorbs heat from the surroundings in an endothermic reaction has a positive \DeltaH. - examples of endothermic processes: Melting ice cubes. Melting solid salts. Sublimation of dry ice into carbon dioxide gas. Evaporating liquid water.