1. The Mole Concept & Stoichiometry
Mole Calculation Example:
Formula: Number of moles \(n = \frac{\text{Mass } (g)}{\text{Molar Mass } (g/mol)}\).
Question: Calculate the number of moles in 22g of Carbon Dioxide (\(\text{CO}_2\)). [Ar: C=12, O=16]
Solution:
1. Molar Mass \(M_r(\text{CO}_2) = 12 + (2 \times 16) = 44\text{ g/mol}\).
2. Moles \(n = \frac{22}{44} = \mathbf{0.5\text{ moles}}\).
Formula: Number of moles \(n = \frac{\text{Mass } (g)}{\text{Molar Mass } (g/mol)}\).
Question: Calculate the number of moles in 22g of Carbon Dioxide (\(\text{CO}_2\)). [Ar: C=12, O=16]
Solution:
1. Molar Mass \(M_r(\text{CO}_2) = 12 + (2 \times 16) = 44\text{ g/mol}\).
2. Moles \(n = \frac{22}{44} = \mathbf{0.5\text{ moles}}\).
2. Organic Chemistry: Hydrocarbons
- Alkanes: Saturated hydrocarbons with single bonds (\(\text{C}_n\text{H}_{2n+2}\)). E.g., Methane (\(\text{CH}_4\)), Ethane (\(\text{C}_2\text{H}_6\)).
- Alkenes: Unsaturated hydrocarbons with double bonds (\(\text{C}_n\text{H}_{2n}\)). Turn bromine water from brown to colorless.
- Alcohols: Contain the \(\text{-OH}\) functional group. E.g., Ethanol (\(\text{C}_2\text{H}_5\text{OH}\)).
3. Electrochemistry & Electrolysis
Understanding cathode (reduction/gain of electrons) and anode (oxidation/loss of electrons) reactions during copper refining and water electrolysis.