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MS1.

- Reversible reaction (1)

- Forward and reverse reactions occur at the same rate (1)

MS2.

- Le Chatelier's principle: If a change of condition is applied to a system in equilibrium, the position of equilibrium will shift to counteract the change (2)

- Example: Adding more reactants to a system in equilibrium will shift the position of equilibrium to the products' side (1)

MS3.

- Chemical equation: NH3(g) <=> H+(g) + NH2-(g) (1)

- Concentration: Concentration of ammonia decreases (3)

MS4.

- Catalyst speeds up both forward and reverse reactions equally (2)

- No change in position of equilibrium (1)

MS5.

- Chemical equation: CaCO3(s) <=> Ca2+(aq) + CO32-(aq) (1)

- Kc expression: Kc = [Ca2+][CO32-] / [CaCO3] (1)

- Substitution and calculation: Kc = 0.0100 × 0.0100 / 0.100 = 1.00 × 10^-4 (1)

MS6.

- Resists changes in pH when small amounts of acid or base are added (2)

MS7.

- Increase pressure: Shift to products' side (1)

- Decrease temperature: Shift to reactants' side (1)

- Add more reactants (nitrogen and hydrogen): Shift to products' side (1)

MS8.

- Chemical equation: FeSO4(aq) + 2NaOH(aq) <=> Fe(OH)2(s) + Na2SO4(aq) (2)

- Color change: Fe(II) ions are pale green, while Fe(OH)2 is dark green (2)

MS9.

- Chemical equation: MgCO3(s) <=> Mg2+(aq) + CO32-(aq) (1)

- Ksp expression: Ksp = [Mg2+][CO32-] (1)

- Substitution and calculation: Ksp = 0.0050 × 0.0050 = 2.50 × 10^-8 (1)

MS10.

- Saturated solution: Solution in which the maximum amount of solute has been dissolved (1)

- Unsaturated solution: Solution in which not all of the solute has been dissolved (1)