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The shape of an s-orbital is spherical. S-orbitals are spherically symmetric, meaning that the wave function only depends on the distance from the nucleus, not the direction. The s-orbital is spherical due to its lack of angular dependence and zero angular momentum (l=0), meaning the probability of finding an electron is the same in all directions from the nucleus.

\alpha - particle is represented by He atom with mass number of 4 and atomic number of 2. Thus, try to balance the mass number and atomic number of both Ra and Rn by subtracting 4 from 226 i.e (226 - 4) and subtracting 2 from 88 i.e (88 - 2 = 86 ). \(^{226}\)\(_{88}\)Ra → \(^{222}\)\(_{86}\)Rn + \(^4\)\(_2\)He (\alpha - particle)

Electronegativity is the tendency of an atom to attract electrons when forming a chemical bond. In HCl, the chlorine atom's higher electronegativity causes it to attract the bonding electrons, resulting in a partial negative charge on chlorine and a partial positive charge on hydrogen.

Two isotopes of Chlorine are : \(^{35}\)Cl and \(^{37}\)Cl Atomic mass of Cl : 35.5 Ratio of the isotopes of Chlorine : 3 : 1 Let the relative atomic abundance of \(^{37}\)Cl = 1 x X = X Let the relative atomic abundance of \(^{35}\)Cl = 3 x X = 3X N.B : The average atomic mass = sum of products of each isotope mass and its relative abundance. A.M.M = (3x of 35) + (x of 37) 35.5 = (3x X 35) + (x X 37) 35.5 = 105x + 37x 35.5 = 142x x = \(\frac{35.5}{142}\) x = 0.25 Convert to percentage. Recall that relative atomic abundance of \(^{37}\)Cl = x = 0.25 x 100 = 25% and the relative atomic abundance of \(^{35}\)Cl = 3X = 3(0.25) = 0.75 x 100 = 75% We were asked for the Relative abundance of isotope of mass number 37 i.e \(^{37}\)Cl is 25% Alternatively, Ratio of the isotopes of Chlorine : 3 : 1 Sum of ratios = 3 + 1 = 4 Relative Abundance of Cl isotopes = % ratio of \(^{35}\)Cl and % ratio of \(^{37}\)Cl = \(\frac{3}{4}\)x 100 and \(\frac{1}{4}\) x 100 = 75% \(^{35}\)Cl and 25% \(^{37}\)Cl Relative abundance of \(^{37}\)Cl = 25

When heated, a mixture of hydrogen and neon gases emits light and burns in a flame.When heated, the atoms in the gas absorb energy, causing the electrons to jump to higher energy levels. When the electrons return to their original energy levels, they emit light. A mixture of helium and nitrogen does not burn in a flame because both helium and nitrogen are non-flammable. A mixture of helium and neon does not burn in a flame because helium and neon are non-reactive. A mixture of neon and nitrogen will not burn in a flame because neither neon nor nitrogen are flammable.

Water hardness is caused by the presence of positively charged metallic ions, most commonly calcium and magnesium. Water becomes hard when it comes into contact with limestone and other rocks that contain calcium compounds. For example, rainwater that flows over rocks on its way to a reservoir can pick up calcium and magnesium ions.

Acidic conditions can increase the solubility of metal ions in soil, thereby allowing them to leach into groundwater. Also, trioxonitrate(v) salts are generally the only soluble salts of some metals. All trioxonitrate(v) salts are soluble in water. However, nitrates can also contribute to water pollution, but they're more commonly associated with eutrophication and health issues rather than directly mobilizing metal ions. Consequently, acidity plays a significant role in mobilizing metal ions, making them more likely to contaminate groundwater.

Carcinogenic substances, also known as carcinogens, are agents that can cause cancer. Examples include tobacco smoke, alcohol, asbestos, and certain chemical compounds like benzene and asbestos. Asbestos is generally considered more carcinogenic than sawdust. Asbestos, particularly the amphibole fibers, is a known human carcinogen and has been linked to mesothelioma, lung cancer, and other cancers. While wood dust is also classified as a human carcinogen, primarily associated with nasal cancer, the carcinogenic potential of asbestos is considered higher.

Relative molecular mass of CuSO\(_4\) = 64 + 32 + (16 x 4) = 160 The number of moles of CuSO\(_4\) = \(\frac{mass}{Molar mass}\) = \(\frac{20}{160}\) n = 0.125 mole 100g of water dissolved 0.125mole of CuSO\(_4\) 100g of water will dissolve \(\frac{0.125}{100}\times{1000}\) Solubility = 1.25 moldm\(^{-3}\) Alternatively, Solubility = Number of moles of solute x \(\frac{1000}{Volume of solvent}\) But Number of moles of solute = \(\frac{mass}{molar mass}\) = \(\frac{20}{160}\) = 0.125 moles Solubility = Number of moles of solute x \(\frac{1000}{Volume of solvent}\) Solubility = 0.125 x \(\frac{1000}{100}\) = 1.25 moldm\(^{-3}\)

Calcium sulphate is only slightly soluble in water, meaning that only a small amount of it will dissolve, and the rest will remain as a solid. Calcium sulfate in water forms a precipitate, not a suspension. While calcium sulfate is only slightly soluble in water, it does not form a true suspension where particles are suspended in the liquid. Instead, it generally forms a precipitate, which is a solid that separates from the solution and settles at the bottom. When calcium tetraoxosulphate(VI) dissolves sparingly in water, a precipitate is formed. Colloids and precipitates are both related to the separation of substances in a mixture, but they differ in particle size and the process that leads to their formation. Colloids are mixtures where particles are dispersed throughout another substance, but don't settle out quickly. Precipitates, on the other hand, are solid substances that form and separate from a solution during a chemical reaction.

A normal salt is formed when a metal or a group of elements behaving like a metal completely replaces replaceable hydrogen atoms in an acid molecule. Na\(_2\)CO\(_3\) (sodium carbonate), also known as washing soda or soda ash, is a type of normal salt. It's formed from a strong base (sodium hydroxide) and a weak acid (carbonic acid), making it a basic salt.

First, write a balanced equation for the chemical reaction: 2NaOH + H\(_2\)SO\(_4\) → Na\(_2\)SO\(_4\) + 2H\(_2\)O From the balanced equation, N\(_A\) = 1 ; N\(_B\) = 2 C\(_A\) = 0.5 moldm\(^{-3}\) ; V\(_A\) = ? ; C\(_B\) = 0.1 moldm\(^{-3}\) ; V\(_B\) = 20 cm\(^3\) Using the formula, \(\frac{{C_A}{V_A}}{{C_B}{V_B}}\) = \(\frac{N_A}{N_B}\) V\(_A\) = \(\frac{{C_B}{V_B}{N_A}}{{C_A}{N_B}}\) = \(\frac{{0.1}\times{20}\times{1}}{{0.5}\times{2}}\) V\(_A\) = 2.0 cm\(^3\)

The Oxidation state of H= +1 , O = - 2 , Cl = ? HClO\(_4\) = 0 +1 + Cl + (- 2 x 4) = 0 Cl = +8 - 1 Cl = + 7

A substance is reduced when it gains electrons or loses oxygen.i,e it undergoes reduction. while a substance is oxidized, when it loses electrons, gains oxygen, or has hydrogen removed. Therefore, Zn is reduced because it lost oxygen.

SO\(_2\) can act as both an oxidizing and reducing agent because it has multiple valencies, with the oxidation state of sulphur ranging from -2 to +6. It can oxidize hydrogen sulphide to sulphur, and carbon monoxide to carbon dioxide. It can lose electrons to other compounds, reducing itself to a lower valency state. For example, SO\(_2\) can reduce ferric to ferrous salts, and acidified potassium iodate to iodine. Therefore, sulphur dioxide, SO\(_2\) can act as both an oxidizing and reducing agent.