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Soaps are made up of a fatty acid with a long alkyl chain and a '-COONa' group, while detergents are made up of a long alkyl chain and a '-SO3 Na\(^+\) group. The polar sulfonate in detergents makes them more soluble in hard water than soaps because it's less likely to bind to calcium and other ions in hard water.

Organic solvents, such as alcohol, chloroform, petroleum ether, and hexane, can dissolve fats and oils. Other organic solvents that can dissolve fats include: benzene, diethylether, and tetrachloromethane. Kerosene also falls within this category of non-polar solvents. Fats are insoluble in water because they are hydrophobic and do not have polar bonds. Water is a polar molecule, meaning that the oxygen atom has a partial negative charge and the hydrogen atoms have partial positive charges.

1 mole m-3 K2CrO4 contains 194.2g mol-1 in 1000cm3 1 mole m-3 K2CrO4 contains 92.2g mol-1 in 500cm3 1 mole m-3 K2CrO4 contains 48.55g mol-1 in 250cm3 If n molm-3 K2CrO4 contain 48.55 0.02 molm-3 will contain (0.02/1) * (48.55/1) = 0.97g

Biological methods use microorganisms, such as bacteria and fungi, to break down petroleum hydrocarbons. You can till the contaminated soil. This allows for aerobic action that will break down the oil. Wetting the contaminated soil with a bio-friendly detergent will help break down the oil faster. Hydrogen peroxide is also used to aid in breaking down the oil as the oxygen helps the microbes.

Note that Number of moles = \(\frac{mass}{Molar mass}\) n = \(\frac{10}{40}\) = 0.25 mol. ⇒ 0.25 mol of Sodium hydroxide is dissolved in 1000cm\(^3\) = 1 dm\(^3\) i.e 0.25mol dm\(^3\)

A saturated solution is one in which no more solute can be dissolved in a given amount of solvent at a specified temperature and pressure.

If \DeltaH > 0, it simply means it is an endothermic reaction. However, in an endothermic reaction, the reaction will proceed favourably if the temperature is increased.

The commonest feature of reactions at the anode is that oxidation is involved, because electrons are being lost as the substance becomes positively charged.

Adding a catalyst to a chemical reaction lowers the activation energy. A catalyst speeds up a reaction by providing an alternative reaction pathway that requires less energy. This is similar to how an escalator requires less energy to get to a destination than stairs.The catalyst does not change the energy of the reactants or products. It also doesn't change the standard enthalpy change or the Gibbs energy of the reaction.

An oxidizing agent is reduced in a chemical reaction, meaning it gains electrons and its oxidation state decreases. An oxidizing agent, also known as an oxidant or oxidizer, is a substance that causes oxidation by accepting electrons from another compound, called the reducing agent. This process is called reduction, and it makes the oxidizing agent more negative.

An increase in pressure will usually favour the side with a lesser value of total number of moles of gaseous substances, thereby causing the equilibrium position to shift. However, for the equilibrium position to shift to the right if the pressure is increased, it means the total number of moles of the gaseous species on the RHS must be lesser than the total number of moles on the LHS. Consequently, option C is the only option having 2moles of water on the RHS against 3moles on the LHS.

The electrolysis of sodium chloride solution, also known as brine, produces chlorine gas at the anode and hydrogen gas at the cathode. Sodium hydroxide is also formed as a by-product, depending on the concentration of sodium chloride in water. During the electrolysis of a concentrated sodium chloride solution, hydrogen ions are discharged at the cathode and chloride ions are discharged at the anode.

CO + H2O → CO2 + H2 DH = - 394 kJ mol-1 The equation for the standard enthalpy change of formation is \DeltaHreaction = \DeltaH(products) − \DeltaH(reactants) = - 394 - ( - 242 - 110) = - 394 - ( - 352) = - 394 + 352 = - 42 kJ mol-1

The dissolution of sugar in tea is accompanied by positive change in entropy. When there is a change in the state of a substance from solid to liquid, there is an increase in entropy. In general, if a substance changes its structure from a condensed state to a less condensed state, then we say there is an increase in entropy.

An electrolyte is a compound that dissociates into ions in an aqueous solution. When sodium acetate is dissolved in water, it dissociates into sodium cations, Na\(^+\) and acetate anions CH\(_3\)COO\(^-\). Sodium acetate is a strong electrolyte in an aqueous solution.