Answer:
The answer to your question is letter E. 288.4 g/mol
Explanation:
Data
Number of carbons = 19
mass percent of carbon = 79.12
molar mass = ?
Process
1.- Calculate the molar mass of 19 atoms of carbon
Atomic mass of carbon = 12 g
Atomic mass of 19 atoms of carbon = 228 g
2.- Use proportions to calculate the mass of testosterone
228 g --------------- 79.12 %
x -------------- 100 %
x = (228 x 100) / 79.12
Simplify
x = 22800 / 79.12
Molar mass of testosterone = 288.2 g
Answer:
what to do in this question
Answer:
At the burner temp. and pressure, 18.85 litres of air is needed to completely combust each gram of propane
Explanation:
The combustion stoichiometry is as follows:
C₃H₈ + 5O₂ = 4 H₂O + 3CO₂ The molecular weights (g/mol) are:
MW 44 5x32 4x18 3x44
So each gram of propane is 1/44 = 0.02272 mol propane
and will need 5 x 0.02272 = 0.1136 mol oxygen
At 0.21 mol fraction oxygen in air, 0.1136 / 0.21 = 0.54 mol air is needed to burn the propane.
At the low pressure in the burner we can use the Ideal Gas Law
PV=nRT, or V = nRT/P
P = 1.1 x 101325 Pa = 111457 Pa
T = 195°C + 273 = 468 K
R = 8.314
and we calculated n = number of moles air = 0.54 mol
So V m³ = 0.54 x 8.314 x 468 / 111457 = 0.0188 m³ = 18.85 litres air.
Answer:
Number of particles = 2.0 g*(6.0 x 10^23 particles/mol) / 20.18 g/mol
Option C is correct
Explanation:
Step 1: Data give
Mass of Ne = 2.0 grams
Molar mass of neon = 20.18 g/mol
Number of Avogadro = 6.0 *10^23 /mol
Step 2: Calculate number of moles of neon
Moles Ne = Mass of ne / Molar mass of ne
Moles Ne = 2.0 / 20.18 g/mol
Moles Ne = 0.099 moles
Step 3: Calculate nulber of particles
Number of particles = 6.022*10^23 / mol * 0.099 moles = 5.96 *10^22
Number of particles = 6.022*10^23 * (2.0g/ 20.18g/mol)
Number of particles = 2.0 g*(6.0 x 10^23 particles/mol) / 20.18 g/mol
Option C is correct