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Cracking is a chemical process in which larger hydrocarbon molecules are broken down into smaller and more useful ones. This process is commonly used in petroleum refining to convert heavy hydrocarbons into lighter fractions, including alkenes. During cracking, high-temperature and/or catalytic conditions are applied to break the long carbon chains of hydrocarbons into shorter ones. This process produces a mixture of products, including alkenes, which are unsaturated hydrocarbons containing carbon-carbon double bonds.

The formation of a bond between hydrogen and a highly electronegative atom results in polarity because the electronegative atom will attract the shared pair of electrons more than the hydrogen atom, creating a dipole with a partial negative charge on the electronegative atom and a partial positive charge on the hydrogen atom.

Among the given elements, W has the lowest ionization energy (\(12.0 KJ mol^{-1} x 10^{-3})\), indicating that it would be more likely to react with chlorine. X has a higher ionization energy \((21.0 KJ mol^{-1} x 10^{-3})\), so it would be less reactive with chlorine compared to W. Based on ionization energy values, the elements that would react more readily with chlorine are W and X.

They completely dissociate into ions in solution. Strong electrolytes are substances that fully dissociate into ions when dissolved in water or melted. As a result, they produce a high concentration of ions in the solution, allowing for efficient electrical conductivity.

The correct answer is (b). The second energy level (n=2) can hold a maximum of 8 electrons. It consists of two subshells, 2s and 2p, which can hold 2 and 6 electrons, respectively.

Phenolphthalein is a common laboratory indicator used to detect the presence of bases in a solution. In its basic form (pH > 8.3), it turns pink or purple, indicating the presence of a base.

Molar mass of \(C_2H_4O_2\),= (12 \times 2) + (1 \times 4) + (16 \times 2)= 60 g/mol Vapour density = RMM/2 =60/2=30

In general, solids are relatively incompressible compared to liquids and gases. When pressure is applied to a solid, there is typically only a small change in volume. Solids have tightly packed particles with strong intermolecular forces, making them less responsive to changes in pressure. Liquids and gases, on the other hand, can undergo larger volume changes in response to pressure.

Polymerization is a process in which small molecules combine to form larger molecules. This process is not consistent with the kinetic theory of matter because it does not involve the movement of particles. The particles in a polymer are not moving randomly. They are bonded together in a fixed structure. Therefore, the property that does not give evidence of the kinetic theory of matter is polymerization.

Dilute trioxonitrate (V) acid does not produce hydrogen when it reacts with metals because it is a strong oxidizing agent. Trioxonitrate (V) acid, also known as nitric acid, is a strong oxidizing agent. This means that it can easily oxidize metals, which means that it can remove electrons from metals. When nitric acid oxidizes a metal, it forms salt and water. The salt does not contain hydrogen, so no hydrogen gas is produced

The general formula for alkanes is \(C_nH_{2n}+2\). For an alkane with 49 carbon atoms (n = 49), the number of hydrogen atoms can be calculated as follows: Number of hydrogen atoms (H) = 2n + 2 Number of hydrogen atoms (H) = 2 * 49 + 2 Number of hydrogen atoms (H) = 98 + 2 Number of hydrogen atoms (H) = 100 So, an alkane with 49 carbon atoms contains 100 hydrogen atoms.

Crystallization is a separation technique that exploits differences in the solubilities of components in a solution. When a solution is allowed to cool or evaporate under controlled conditions, one of the salts may begin to crystallize out of the solution before the other due to its lower solubility. This process can be used to separate the salts based on their differing solubilities and crystal formation.

In a chemical reaction, intermediates are the chemical species that are formed during the reaction but are subsequently consumed in further steps, leading to the final products. They are transient species that exist momentarily during the reaction process and are not present in the initial reactants or the final products of the overall reaction.

Number of moles = Mass / Molar mass Given that the molar mass of oxygen \(O_2\) is 32.0 g/mol (2 \times 16.0 g/mol), you can calculate the number of moles: Number of moles = 3.0 g / 32.0 g/mol = 0.09375 moles Rounded to four significant figures, the number of moles in 3.0 g of O2 is approximately 0.0938 moles. Therefore, the closest answer choice is: 0.0930 moles.

\(H_2SO_4\)(aq) is a strong acid that dissociates into two hydrogen ions (H+) and one sulfate ion \(SO4^{2-}\) when dissolved in water. This leads to a higher concentration of ions in the solution, resulting in higher conductivity.