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When an ammonium salt dissolves in water, the resulting solution is acidic. Ammonium ions (NH\(_4\)\(^+\)) act as a weak acid when dissolved in water, donating a proton to water molecules and creating hydronium ions (H\(_3\)O\(^+\), which lowers the pH and makes the solution acidic.Consequently, option B is correct since the pH of solution formed will be less than 7 not greater than 1 because greater than 1 can mean that it is alkaline. Ammonium salts decompose when heated, typically releasing ammonia gas as one of the products. Ammonium salts break down into their constituent components, like ammonia and the corresponding acid, when exposed to heat. For example, ammonium chloride (NH\(_4\)Cl) decomposes into ammonia (NH\(_3\)) and hydrogen chloride (HCl) when heated. Ammonium salts are generally very soluble in water; most simple ammonium salts readily dissolve in water, making them considered highly soluble. Which makes the statement incorrect.

Solid ethanedioic acid (also known as oxalic acid) is typically purified through a process called crystallization where the impure solid is dissolved in a hot solvent (usually water), then allowed to cool slowly, causing the purer crystals to precipitate out while leaving impurities behind in the solution; this process can be repeated multiple times for further purification.

To identify an alkanoic acid, look for the presence of the carboxyl functional group (-COOH) in the molecule, which is the key indicator of an alkanoic acid (also known as a carboxylic acid).

The primary intermolecular force between ethanol molecules is hydrogen bonding. Hydrogen bonding is a strong type of dipole-dipole attraction. Other intermolecular forces present in ethanol is the London dispersion forces or Van der waal's force. Van der Waals forces of attraction are present in ethanol molecules, alongside stronger hydrogen bonding interactions; essentially, all molecules experience some degree of van der Waals forces, making them present in ethanol as well.

If 0.24g of the salt was dissolved in 100 cm\(^3\) then Xg of the salt will be dissolved in 1000 cm\(^3\) (1 dm\(^3\) ⇒ 0.24 = 100 cm\(^3\) X = 1000 cm\(^3\) Solubility of salt, X (gdm\(^{-3}\)) = \(\frac{{0.24} \times{1000}}{100}\) = 2.40 gdm\(^{-3}\)

Ni\(^{2+}\)\(_{aq}\) + Fe\(_s\) → Ni\(_s\) + Fe\(^{2+}\)\(_{aq}\) Reduction takes place from Ni\(^{2+}\) to Ni because there is a decrease in oxidation number from +2 to 0. Thus, Ni\(^{2+}\) ions are reduced to Ni Oxidation takes place from Fe to Fe\(^{2+}\) because there is an increase in oxidation number from 0 to +2. Thus, Fe is oxidized to Fe\(^{2+}\) Oxidizing agent → Ni\(^{2+}\) because oxidizing agents undergo reduction. Reducing agent → Fe because reducing agents undergo oxidation. Consequently, option D is the correct option.

Transition elements are elements having partially filled d- orbitals. The first series of transition elements ranges from Scandium to Zinc. Apart from the general properties of metals, the transition elements have in addition the following characteristics: - Variable oxidation state - Catalytic properties - Magnetic properties. - Complex ion formation

Aluminum is ideal as an alloy for aircraft because it strikes a great balance between being lightweight, strong, resistant to corrosion, and relatively easy to work with, making it perfect for building large aircraft structures while minimizing overall weight, which significantly improves fuel efficiency and performance; this is especially important due to its high strength-to-weight ratio compared to other metals like steel.

Ionization energy is said to be the amount of energy required to remove a valence electron from the atom of an element to become a gaseous specie. Ionization energy decrease as you move down the group and increase across the period in the periodic table. Consequently, the elements under consideration are in the same period, period 3, ranging from Aluminium to Silicon to Phosphorus to Sulphur. i.e Al < Si < P < S.

C\(_3\)H\(_8\) + 5 O\(_2\) → 3CO\(_2\) + 4H\(_2\)O From the equation: 1 mole : 3 moles If 0.1 mole reacted, then 0.3 mole will be formed. ⇒ 0.3 mole of CO\(_2\) will be produced. Recall that Number of moles of gases = \(\frac{Volume}{Molar Volume of gas at stp}\) n = \(\frac{V}{M.V}\) 0.3 = \(\frac{V}{22.4}\) V = 0.3 x 22.4 V = 6.72 dm\(^3\)

Relative Atomic Mass of Boron = [19.9% \(^{10}\)B} + [80.1% \(^{11}\)B] = [ 19.9% of 10] + [80.1% of 11] = [ \(\frac{19.9}{100}\times{10}\) ] + [ \(\frac{80.1}{100}\times{11}\)] = 1.99 + 8.811 = 10.801

In methane (CH\(_4\)), there are four shared pairs of electrons. A single carbon atom in the center shares one pair of electrons with each of the four hydrogen atoms, resulting in four shared pairs.

Isotopes differ in the number of neutrons in their nucleus, but they have the same number of protons (which determines the number of electrons). Since chemical properties are primarily determined by the electron configuration, isotopes of the same element behave similarly in chemical reactions.

Milk of magnesia is alkaline because it has a pH of 10.5, which means that it would neutralize any acidic substance encountered. Hence, it is an excellent antacid. It neutralizes excess stomach acid or hydrochloric acid. The hydroxide ions of the milk combine with the hydrogen ions in the stomach acid to reduce excess acidity in the stomach.

Given: M\(_r\) of MgSO\(_4\).7H\(_2\)O = 246 M\(_r\) of Oxygen = 16 Percentage by mass of Oxygen = \(\frac{Total mass of Oxygen}{Total mass of MgSO_4.7H_2O}\times 100\) % by mass of Oxygen = \(\frac{11moles of oxygen}{MgSO_4.7H_2O}\times 100\) (4moles of oxygen + 7 moles of oxygen from 7H\(_2\)O ) = \(\frac{11 X 16}{246}\times 100\) = \(\frac{176}{246}\times 100\) = 71.544% = 71.5%