Okay ...................x
For a hydrocarbon, the combustion reactions are the following:
C + O₂ --> CO₂
H₂ + 1/2 O₂ --> H₂O
The molar mass of CO₂ is 44 g/mol while C is 12 g/mol. Let's solve for amount of C in hydrocarbon.
Mass of C = (14.1 g CO₂)(1mol/44g)(1 mol C/1 mol CO₂)(12 g/mol) = 3.845 g C
So, that means that the mass of hydrogen is:
Mass of H = 4.4 - 3.845 = 0.555 g
Moles C = 3.845/12 = 0.32042
Moles H = 0.555/1 = 0.555
Divide both by the smaller value, 0.32042.
C: 0.32042/0.32042 = 1
H: 0.555/0.32042 = 1.732
We have to get an answer that is closest to a whole number. Let's try multiplying both with 4.
C: 1*4 = 4
H: 1.732*4 = 6.93≈7
<em>Thus, the empirical formula is C₄H₇.</em>
Answer:
D) 174 g/mol
Explanation:
Step 1: Given and required data
- Density of the gas (ρ): 7.10 g/L
- Ideal gas constant (R): 0.0821 atm.L/mol.K
Step 2: Convert "T" to Kelvin
We will use the following expression.
K = °C + 273.15
K = 25.0°C + 273.15
K = 298.2 K
Step 3: Calculate the molecular weight (M) of the gas
We will use the following expression derived from the ideal gas equation.
ρ = P × M / R × T
M = ρ × R × T / P
M = 7.10 g/L × (0.0821 atm.L/mol.K) × 298.2 K / 1.00 atm
M = 174 g/mol
Answer:
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