Persamaan Gas Ideal

\(\text{PV} = \text{nRT}\) \(2\text{ atm}\cdot 4,1 \text{ liter} = \text{n} \cdot (0,082 \text{ L.atm/mol. K}) \cdot (27 + 273 \text{K})\) \(8,2 = \text{n} \cdot 0,082 \cdot 300\) \(8,2 = \text{n} \cdot 24,6\) \(\text{n} = \dfrac{8,2}{24,6} \text{ mol}\) \(\text{n} = \dfrac{1}{3} \text{ mol}\) Jumlah mol gas oksigen dalam tabung adalah \(\dfrac{1}{3} \text{ mol}\)   \(\text{n} = \dfrac{\text{massa oksigen}}{\text{Mr } \ce{O2}}\) \(\dfrac{1}{3} = \dfrac{\text{massa oksigen}}{2\times 16}\) \(\dfrac{1}{3} = \dfrac{\text{massa oksigen}}{32}\) \(\text{massa oksigen} = \dfrac{32}{3} = 10,67 \text{ gram}\)

Gas metana = \(\ce{CH4}\) \(\text{Mr } \ce{CH4} = 1\times \text{Ar C} + 4 \times \text{Ar H}\) \(\text{Mr } \ce{CH4} = 1\times 12 + 4 \times 1\) \(\text{Mr } \ce{CH4} = 16\)   \(\text{Tekanan } = 76 \text{ cmHg} = 1 \text{ atm}\) \(\text{Volume } = 8200 \div 1000 \text{ liter} = 8,2 \text{ liter}\) \(\text{Suhu  } = 127 + 273 = 400 \text{ K}\)   \(\text{PV} = \text{nRT}\) \(1\text{ atm}\cdot 8,2 \text{ liter} = \text{n} \cdot (0,082 \text{ L.atm/mol. K}) \cdot 400 \text{ K}\) \(8,2 = \text{n} \cdot 0,082 \cdot 400\) \(8,2 = \text{n} \cdot 32,8\) \(\text{n} = \dfrac{8,2}{32,8} \text{ mol}\) \(\text{n} = \dfrac{1}{4} \text{ mol}\) Jumlah mol gas metana dalam tabung adalah \(\dfrac{1}{4} \text{ mol}\)   \(\text{n} = \dfrac{\text{massa metana}}{\text{Mr } \ce{CH4}}\) \(\dfrac{1}{4} = \dfrac{\text{massa metana}}{16}\) \(\text{massa metana} = \dfrac{16}{4} = 4\text{ gram}\)