Sebanyak 2 gram gas nitrogen berada dalam suatu wadah tertutup pada kondisi suhu 0°C dan tekanan 1 atm. Tentukan volume gas nitrogen dalam wadah tersebut. (Ar N = 14).
\(\text{V} = \text{n}\times 22,4 \text{ liter/mol}\)
\(\text{V} = \dfrac{\text{massa nitrogen}}{\text{Mr }\ce{N2}}\times 22,4 \text{ liter/mol}\)
\(\text{V} = \dfrac{2 \text{ gram}}{2 \times 14 \text{ gram/mol}}\times 22,4 \text{ liter/mol}\)
\(\text{V} = \dfrac{2}{28}\times 22,4 \text{ liter}\)
\(\text{V} = \dfrac{1}{14}\times 22,4 \text{ liter}\)
\(\text{V} = \dfrac{22,4}{14}\text{ liter}\)
\(\text{V} = \dfrac{224}{140}\text{ liter}\)
\(\text{V} = 1,6 \text{ liter}\)
Sebanyak 112 liter gas etana berada dalam suatu wadah tertutup pada kondisi suhu 0°C dan tekanan 1 atm. Tentukan massa gas etana dalam wadah tersebut. (Ar C = 12, Ar H = 1).
Gas etana = \(\ce{C2H6}\)
\(\text{V} = \text{n}\times 22,4 \text{ liter/mol}\)
\(\text{V} = \dfrac{\text{massa gas etana}}{\text{Mr }\ce{C2H6}}\times 22,4 \text{ liter/mol}\)
\(112 \text{ liter} = \dfrac{\text{massa gas etana}}{2 \times 12 + 6\times 1 \text{ gram/mol}}\times 22,4 \text{ liter/mol}\)
\(112 = \dfrac{\text{massa gas etana}}{30}\times 22,4\)
\(\cancelto{5}{112} = \dfrac{\text{massa gas etana}}{30}\times \cancel{22,4}\)
\(5 = \dfrac{\text{massa gas etana}}{30}\)
\(\text{massa gas etana} = 5 \times 30 \text{ gram}\)
\(\text{massa gas etana} = 150 \text{ gram}\)
Suatu gas diatomik memiliki volume 4,48 liter berada dalam suatu wadah tertutup pada kondisi suhu 0°C dan tekanan 1 atm. Jika massa gas tersebut 14,2 gram, tentukan massa atom relatif gas tersebut.
Misal gas diatomik tersebut = \(\ce{X2}\)
\(\text{V} = \text{n}\times 22,4 \text{ liter/mol}\)
\(\text{V} = \dfrac{\text{massa gas}}{\text{Mr }\ce{X2}}\times 22,4 \text{ liter/mol}\)
\(4,48 \text{ liter} = \dfrac{14,2}{2 \times \text{Ar X} \text{ gram/mol}}\times 22,4 \text{ liter/mol}\)
\(4,48 = \dfrac{14,2}{2 \times \text{Ar X}}\times 22,4 \)
\(\dfrac{4,48}{22,4} = \dfrac{14,2}{2 \times \text{Ar X}}\)
\(\dfrac{1}{5} = \dfrac{14,2}{2 \times \text{Ar X}}\)
Kalikan silang,
\(2 \times \text{Ar X} = 5 \times 14,2\)
\(2 \times \text{Ar X} = 71\)
\(\text{Ar X} = 71 \div 2 \text{ gram/mol}\)
\(\text{Ar X} = 35,5 \text{ gram/mol}\)
Jadi, massa atom relatif gas diatomik tersebut adalah 35,5
