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The rate of dimension of a gas inversely proportional to the square root of its molecular mass or its density, which is Graham's Law of diffusion of gas. R ∝ \(\frac{1}{\sqrt{Mm}}\) or R ∝ \(\frac{1}{\sqrt{D}}\) Dx = 0.5gdm-3, Dy = 2gdm-3 R= \(\frac{K}{\sqrt{D}}\) R\(\sqrt{D}\) = k R1\(\sqrt{D_1}\) = R1\(\sqrt{D_2}\) Rx\(\sqrt{D_x}\) = Ry\(\sqrt{D_y}\) \(\frac{R_x}{R_y}\) = \(\frac{\sqrt{D_y}}{\sqrt{D_x}}\) = \(\frac{\sqrt{2}}{\sqrt{0.5}}\) = 2.0

Alkane's family are sp3 hybridized

Where −273°c = OK i.e −273°c + 273 = OK At zero kelvin, the volume of a gas becomes zero.

Molecular mass = vapour density X2 Mm of XO2 = x + 16(2) = x + 32 vapour density = 32 ∴ x + 32 = 32 × 2 x + 32 = 64 x = 64 - 32 x = 32 ∴ the relative molecular mass of X is 32 Relative molecular mass = vapour density × 2

Upward delivery works well for hydrogen and ammonia, which are both less densed than air. Sometimes, they are collected over water.

Bubbling of air through the acid solution removes deposited oxides of nitrogen. Nitric acid is prepared in the laboratory by heating a nitrate salt with the concentrated acid. NaNO3 + H2SO4 → NaHSO4 + HNO3 Vapours of nitric acid are condensed to a brown liquid in a receiver cooled under cold water. "Dissolved oxides of nitrogen" e.g NO2 are removed by redistillation or blowing a current of carbondioxide or dry air through the warm acid

protons = 9 neutrons = 10 electrons = 10 Electronic configuration = 2, 8 Ground state Electronic configuration=2, 7 It means that the atom has gained an electron thereby making it have a negative ion. When an atom donates an electron, it becomes positively charged. When an atom accepts an electron, it becomes negatively charged

Ethene is produced from cracking which involves breaking up large hydrocarbon molecules into smaller and more useful bits. This is achieved by using high temperatures and pressures without a catalyst. C15H32 → 2C2H4 + C3H6 + C8H14 ......Δheat...ethene........propene.........octane

For an ideal gas PV = nRT Amount in moles = n Volume v = 10.5dm3 Pressure P = 6atm Temperature T = 30^\circC + 273 = 303k R, Gas constant = 0.082 atmdm3k-1 mol Recall from ideal gas equation pv = nRT n = \(\frac{RV}{RT}\) n = \(\frac{6 \times 10.5}{0.082 \times 303}\) n= 2.536mol

Rate of diffusion \(\frac{\alpha_1}{Density}\) or \(\frac{1}{\sqrt{Mm}}\) Rate = \(\frac{1}{time}\) \(\frac{1}{time}\) \(\frac{\alpha_1}{Density}\) or \(\frac{1}{\sqrt{Molarmass}}\) Time \(\alpha \sqrt{Density}\) or \(\sqrt{Molarmass}\) At constant volume of 100cm3 \(\frac{t_{o2}}{\sqrt{Mn_{o2}}}\) = \(\frac{t_{n2}}{\sqrt{1 \times 2}}\) \(\frac{50}{4 \sqrt{2}}\) = \(\frac{t_{n2}}{\sqrt{2}}\) tn2= 12.5s

Na is kept under kerosene (paraffin) to avoid reactivity with air. Paraffin is also known as Kerosene. Na(sodium) is kept in kerosene to prevent it from coming in contact with oxygen and moisture. If this happens, it will react with the moisture present in air and form sodium hydroxide.

Furring of kettles is caused by the temporary hardness in water. Temporary hardness in water is caused by calcium and magnesium trioxocarbonate (IV) CaCO3 causes the furring of kettles

Chlorine helps to keep water from germs and bacteria.

Balancing the chemical equation. Ca[OH]2 + 2NH4Cl → CaCl2 + 2H2O + 2NH3 X = NH3

\DeltaG= \DeltaH − T\DeltaS. To determine whether \DeltaG will be positive or negative, the value of \DeltaH(change in enthalpy) and \DeltaS (change in entropy) must be given. Likewise the temperature. Entropy represents the degree of disorder in a system. In a gaseous reaction, this is determined by the change in the number of moles of gas. Reactants: 1 mole of X + 3 moles of Y = 4 moles of gas Products: 2 moles of Z = 2 moles of gas. The spontaneity of a reaction is determined by the equation: \DeltaG= \DeltaH − T\DeltaS. \DeltaH is positive , T = is always positive, \DeltaS = is negative. Substituting the signs into the equation: \DeltaG= \DeltaH − T\DeltaS = (+) - (T x (-)) = + Since both terms are positive, \DeltaG must be positive regardless of the specific value of T as long as T is expressed in Kelvin (which is always > 0). A positive \DeltaG indicates the reaction is non-spontaneous at room temperature.