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The periodic property that is used to determine whether a covalent molecule is polar or not is electronegativity. Electronegativity is a measure of the ability of an atom to attract electrons in a chemical bond. The greater the electronegativity of an atom, the more strongly it will attract electrons.

Molar mass of Na2SO4 = 2(Na) + S + 4(O) = 2(23.0 g/mol) + 32.1 g/mol + 4(16.0 g/mol) = 46.0 g/mol + 32.1 g/mol + 64.0 g/mol = 142.1 g/mol Now, we can calculate the number of moles of Na2SO4 in the solution: Number of moles = Mass of the salt / Molar mass Number of moles = 10.5 g / 142.1 g/mol ≈ 0.0739 mol Next, we need to find the volume of the saturated solution, given as 100 cm³, and convert it to liters: Volume of solution = 100 cm³ = 100 cm³ / 1000 cm³/dm³ = 0.1 dm³ Finally, we can calculate the solubility in mol/dm³: Solubility = Number of moles / Volume of solution Solubility = 0.0739 mol / 0.1 dm³ ≈ 0.739 mol/dm³ Rounded to two decimal places, the solubility of sodium tetraoxosulphate (VI) at 30^\circC is approximately 0.74 mol/dm³. Therefore, the correct option is: 0.74 mol dm-3. Solubility = 10.5 g / 100 cm3 * 142 g/mol = 0.739 mol/dm3

The compound that could be dried by using conc. tetraoxosulphate (VI) acid and not calcium oxide is an acid anhydride. Acid anhydrides are compounds that can react with water to form acids. When acid anhydrides are exposed to air, they will absorb water from the air and become hydrated. This can make them difficult to dry with calcium oxide, which is a base.

The statement that is not correct about gases is Gases are highly soluble in water at high temperatures. Gases are not highly soluble in water at high temperatures. The solubility of gases in water decreases as the temperature increases. This is because the kinetic energy of the gas molecules increases as the temperature increases. The increased kinetic energy of the gas molecules makes it more difficult for them to be dissolved in water.

Molarity = 0.100 mol / 0.250 mol dm3 = 0.100 mol / 0.250 dm3 * 1000 cm3/dm3 = 400 cm3 Volume (V) = Amount (n) / Concentration (C) Given that the amount of HCl is 0.100 mol and the concentration of the solution is 0.250 mol/dm³, you can calculate the volume: Volume (V) = 0.100 mol / 0.250 mol/dm³ = 0.4 dm³ Since 1 dm³ is equal to 1000 cm³, you can convert the volume from dm³ to cm³: Volume (V) = 0.4 dm³ \times 1000 cm³/dm³ = 400 cm³ Therefore, the volume of 0.100 mol of HCl in a 0.250 mol/dm³ solution is 400 cm³.

In metallic bonding, positive metal ions (cations) are surrounded by a "sea" of delocalized electrons that move freely throughout the metal lattice. This arrangement creates a cohesive force that holds the metal atoms together. The mobile electrons contribute to the unique properties of metals, such as high electrical and thermal conductivity, malleability, and ductility.

Isotope \(^{65}X_{30}\) (with a mass of 65 and an abundance of 60%): Relative mass contribution = (65 * 60%) = 39.00 Isotope \(^{66}X_{30}\) (with a mass of 66 and an abundance of 40%): Relative mass contribution = (66 * 40%) = 26.40 Now, add the relative mass contributions of both isotopes: Relative atomic mass \(A_r\) = 39.00 + 26.40 = 65.40 So, the relative atomic mass of element X is 65.40. The correct option is: 65.40

The rate of reaction is proportional to the number of effective collisions. This means that if the number of collisions increases, the rate of reaction will also increase. These successful collisions are known as effective collisions. The rate of reaction is directly proportional to the number of effective collisions between reactant molecules. In other words, the more frequent and successful the collisions, the faster the rate of the reaction.

Sodium is an alkali metal, and its atomic number is 11. This means that it has 11 electrons, and its electron configuration is \(1s^2 2s^2 2p^6 3s^1\). The valence electrons are the electrons in the outermost shell, which in this case is the 3s orbital.

Applied chemistry refers to the practical application of chemical principles and techniques to solve real-world problems and create useful products. Petrochemistry is a branch of applied chemistry that deals specifically with the chemical processes and transformations involved in the extraction, refining, and processing of petroleum and its derivatives

In \(Cl_2\), the two chlorine atoms are identical and have the same electronegativity. Since both atoms have the same electronegativity, the electrons in the covalent bond are shared equally, resulting in a non-polar covalent bond. The molecule does not have a significant separation of charge and lacks a permanent dipole moment.

The reduction half equation for the given reaction is: \(Cu^{2+}_{(aq)} + 2e^- → Cu_{(s)}\) In the overall reaction, copper(II) ions (\(Cu^{2+})\) gain two electrons (2e^-) and get reduced to form solid copper (Cu) metal. This is the reduction half-reaction in the redox reaction between zinc (Zn) and copper(II) sulfate (\(CuSO_4)\).

\(H_2SO_4\) and \(CaCl_2\) are not suitable for drying ammonia gas because they react with the gas. Ammonia is a basic gas, and both \(H_2SO_4\) and \(CaCl_2\) are acidic. When these two substances react, they form salts that contain ammonia. This can contaminate the ammonia gas and make it unusable. In addition, \(H_2SO_4\) is a corrosive substance, and \(CaCl_2\) can be harmful to breathe in. Therefore, it is not safe to use these substances to dry ammonia gas.

The term "isoelectronic" comes from the Greek words "iso" meaning "equal" and "electron" meaning "electron". Isoelectronic species are atoms, molecules, or ions that have the same number of electrons. have the same number of electrons because they have the same electron configuration. The electron configuration of an atom is the arrangement of electrons in the atom's orbitals. The electron configuration of an atom determines the chemical properties of the atom.

The rate of diffusion of a gas is inversely proportional to the square root of its molar mass (Graham's law). This means that gases with a higher molar mass will diffuse more slowly than gases with a lower molar mass. Given the molar masses of the gases in the options, Oxygen (O=16.0) has the highest molar mass and therefore the lowest rate of diffusion