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Table of values/observation \(l_o\) = 0.8A S/N L(cm) l(A) (L\(^{-1}\)cm\(^{-1}\)) 1 25.0 1.20 0.040 2 40.0 1.00 0.025 3 55.0 0.95 0.018 4 70.0 0.85 0.014 5 85.0 0.8 0.012 When 1\(^{-1}\) =0, l = 0.66A \(\frac{|_{o}}{|} = \frac{0.8}{0.66}\) = 1.212 Precautions: The Key was open when readings were not being taken. Tight connections were ensured. Parallax errors were avoided in reading the meter-rule Zero error was noted in reading metre-rule The jockey was not rolled on or allowed to scratch the wire (b) The p.d between two points is the work done (in joules) in moving an electric charge of one coulomb across the two points. ii. R = \(\frac{PL}{A} = \frac{4pL}{\pi d^{2}}\) d = 0.2m, \(\pi\) = \(\frac{22}{7}\), R = 7\(\Omega\), p = 8.8 x 10\(^{-7} \pi \), L = ? \(\therefore\) 7 = \(\frac{4 \times 8.8 \times 10^{-7} \times L}{\frac{22}{7} \times (0.2)^{2}}\) 7 = \(\frac{4 \times 8.8 \times 10^{-7} \times L \times 7}{22 \times 0.04} = \frac{28 \times 8.8 \times 10^{-7} \times L}{0.88}\) L = \(\frac{7 \times 0.88}{28 \times 8.8 \times 10^{-7}}\) L = \(\frac{6.16}{246.4}\) x 10\(^{-7}\) L = 0.025 x 10\(^{7}\) L = 2.5 x 10\(^{-2}\) x 10\(^{7}\) L = 2.5 x 10\(^{5}\)

2KClO3 → 2KCl + 3O2 3 moles of oxygen is produced 1 moles of oxygen is 22.4 dm3 3 moles of oxygen is 67.2 dm3

Option A, C and D are irreversible but option B is reversible because the frozen ice cream can undergo melting and turn into liquid and vice versa, hence no new substance is formed.

Al2(SO4)3. 2H2O 2 * 27 + 3*32 + 14 * 16 + 4 * 1 = 54 + 96 + 224 + 4 = 378 % O2 = (224/378) * (100/1) = 59.25%

The nicotine content is a solute carried by the smoke (mobile phase) and it is removed by the filter (stationary phase) by adsorption. Adsorption is the process by which a solid holds molecules of a gas or liquid or solute as a thin film.

The examiner wishes to test your knowledge on balancing of chemical equation. To balance, calculate the total number of H atom on the RHS, and balance with one on the LHS, you'll discover it's 8. That would be the value of P. Next will be the number of moles of NO on the RHS, you'll discover it is 2. Thus, P = 8 while X = 2 .

Neutral atom of Ne has 10 electrons. Similarly, Mg\(^{2+}\) has 12 protons(atomic number) and 10 electrons because Mg\(^{2+}\) will donate or give out 2 electrons from the 12 and become reduced to 10 electrons. On the other hand, O\(^{2+}\), Ca\(^{2+}\), and K\(^+\) all have 6, 18 and 18 electrons respectively.

Noble gases, also known as inert gases, are chemically inert because their outer electron shells are completely filled with electrons. i.e their octet configuration

Kinetic energy is a measure of the motion of particles, and when temperature increases, the particles absorb energy and move faster. This results in an increase in the kinetic energy of the particles.

Paramagnetic materials are materials that tend to get weakly magnetized in the direction of the magnetizing field when placed in a magnetic field. Paramagnetic elements are elements that have at least one unpaired electron and are slightly attracted to magnetic fields. Examples: Copper, gold, antimony, bismuth, silver, lead, silicon, mercury, water, Oxygen, hydrogen, nitrogen, etc By elimination method, options C and D are eliminated because of Zinc, which is diamagnetic as it has no unpaired electron. Between options A and B, both have H present with difference of Oxygen and Nitrogen, with Oxygen being more paramagnetic than Nitrogen because molecular oxygen (O2) is paramagnetic and is attracted to the magnet. In contrast, molecular nitrogen (N2) has no unpaired electrons and is diamagnetic; it is unaffected by the magnet.

A gas exerts pressure on the walls of the container as the particles of gas move randomly in all directions at high speed. As a result, the particles hit each other and also hit the walls of the container with force. However, gases exert pressure on their containers because the constant, random motion of gas molecules causes them to collide with the container walls, transferring momentum and resulting in a force, which is pressure.

When cathode rays are deflected onto the electrode of an electrometer, the instrument becomes negatively charged. Cathode rays are streams of fast-moving electrons that are negatively charged. When they are deflected towards a positive electrode, it demonstrates that they are negatively charged. This is because opposite charges attract each other.

The weakest attractive force between two molecules is the London dispersion force, also known as an induced dipole-induced dipole attraction. London dispersion forces are a type of van der Waal force, which are weak intermolecular forces that determine the physical and chemical properties of substances

Acids are substances which produces hydrogen ions (or protons) as the only positive ion when dissolved in water. \(H_{3}O^{+} \to 2H^{+} + OH^{-}\)

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.