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Solubility = Amount of solute dissolved in 1dm\(^3\) of solvent divided by the volume of solvent Solubility = \(\frac{mass}{molar mass}\) x 1 dm\(^3\) Molar mass of NaCl = 23 + 35.5 = 58.5 g/mol Solubility = \(\frac{127}{58.5}\) x 1 dm\(^3\) = 2.17 = 2.2 moldm\(^{-3}\)

Ag\(^+\) + e\(^-\) → Ag 1mole = 1F If 1F produced 108g of Ag x F will produce 180g of Ag x = \(\frac{180 x 1}{108}\) x = 1.666 F x = 1.67 F

In an electrolytic refining process, the anode is made of impure metal, and the cathode is made of a strip of pure metal. When an electric current is passed through the electrolyte, metal ions from the electrolyte are deposited as a pure metal on the cathode. A soluble silver salt is used as an electrolyte in the electrolysis of silver metal because it allows for the deposition of a pure metal on the cathode. In the electrolysis of silver metal, you cannot use any rod at the anode; it is crucial to use a silver rod as the anode because the process relies on the oxidation of silver ions from the silver anode into the solution to deposit pure silver at the cathode; using a different metal would not produce the desired result. The net result is that silver metal has been transferred from the anode to the cathode. In summary, a silver rod is used at the anode, the spoon has to be cathode since we must obtain a pure silver spoon while the electrolyte must be a soluble silver salt because it allows easy deposition of metal ions as a pure metal on the cathode.

Iron(III)bromide is the correct answer because Fe has a valency of +3 while Br has a valency of -1, In the bid to form compounds, they bond together and exchange their valency. ⇒ Fe takes the valency of Br which is 1 while Br takes the valency of Fe which is 3. Therefore, the formula for the compound formed should be FeBr\(_3\) and not Fe\(_3\)Br

H\(_2\)SO\(_4\) is a strong acid, so it will completely dissociate into corresponding ions. On dissociation, H\(_2\)SO\(_4\) → 2H\(^+\) + SO\(_4\)\(^{2-}\) If the concentration of H\(_2\)SO\(_4\) is 0.001 M so, the concentration of 2H\(^+\) will be 0.002 M (0.001 x 2). This is because 1 molecule of H\(_2\)SO\(_4\) gives 2H\(^+\) ions. Recall that pH = - Log\(_{10}\)[H\(^+\)] pH = - Log\(_{10}\)[2H\(^+\)] (basicity is 2) = - Log\(_{10}\)[2 x 0.001] = - (Log\(_{10}\)2 + Log\(_{10}\) 0.001) = - (Log\(_{10}\)2 + Log\(_{10}\) 10\(^{-3}\)) Also recall that Log\(_{10}\)2 = 0.3 and Log\(_{10}\)10 = 1 Therefore, pH = - (0.3 - 3) = - ( - 2.7) = 2.7 - Option A

The Aufbau Principle states that, in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy level before occupying higher-energy levels.i.e 1S2S2P.. Hund's rule states that electrons fill orbitals singly before pairing up, and that electrons in singly occupied orbitals have the same spin. The Pauli Exclusion Principle states that, in an atom or molecule, no two electrons can have the same four electronic quantum numbers. The dilution principle is a method for measuring the concentration of a solute in a solution, or the volume of a fluid compartment. Option C is the correct answer.

There are several methods of solving this radioactivity problem. One of the easiest is: \(\frac{Original mass}{2^n}\) = Residual mass Where n = number of activity = \(\frac{exposure time}{half life}\) Given: Original mass = 5g, exposure time = 200 days , half life = 50 days, Residual mass = ? Substituting all the given parameters appropriately, we have n = \(\frac{200}{50}\) n = 4 \(\frac{Original mass}{2^n}\) = Residual mass \(\frac{5}{2^4}\) = Residual mass \(\frac{5}{16}\) = Residual mass Residual mass = 0.3125g = 0.31g

Group VIII also known as inert gases all have their valence shell completely filled with electrons, hence they are referred to as Group O.

Sodium is a metal and X is a non-metal, so the bond between them is ionic. Ionic bonds form when a metal bonds with a non-metal. Element X receives 2 electrons from Na metal and became negatively charged.

The most common isotope of hydrogen, making up more than 99.98% of all hydrogen in the universe. Protium is the lightest isotope of hydrogen and is also known as ordinary hydrogen. Its symbol is 1H. However, the highest isotope of Hydrogen is Tritium \(^3\)T with 1 proton and 2 neutrons.

Water is considered permanently hard when it contains soluble chlorides and sulphates of calcium and magnesium. These salts do not precipitate out when the temperature increases, so boiling the water will not remove them.

Oxygen is not a water pollutant. In fact, oxygen is essential for the survival of life in water. Some examples of water pollutants include: Chemical pollutants: Pesticides, fertilizers, and waste from landfills and septic systems Organic wastes, Microbial contaminants ,Nutrients ,Plastics ,Faecal waste ,Radioactive substances ,Phosphorus and nitrogen.

Fractional distillation is the most common method for separating the gases in air. This method is used because the gases in air have a difference in boiling points of less than 25 K, making them suitable for fractional distillation. Here's how fractional distillation works: 1. Liquefy the gases: Air is converted into liquid air by increasing the pressure and decreasing the temperature. 2. Separate carbon dioxide and water vapour: As the temperature drops below 0^\circC, carbon dioxide separates as dry ice and water vapor separates as ice. 3. Pass the liquid air through a column: The liquid air is then passed through a fractional distillation column, where the gases are separated based on their boiling points.

When sulphur dioxide (SO\(_2\) gas is passed through an acidified potassium permanganate (KMnO\(_4\)) solution, the solution changes from purple to colourless. This is because of a redox reaction, where KMnO\(_4\) acts as an oxidizing agent and SO\(_2\) acts as a reducing agent.

Water gas also known as synthesis gas is obtained from the gasification of coke. It is a flammable, poisonous gas mixture that's made up of carbon monoxide (CO) and hydrogen (H\(_2\)).