Convert all the gases from grams to moles using their molar masses first. Remember that nitrogen and oxygen exist as DIATOMIC gases.
O2 - 25 g / 32 g/mol = 0.78 mol O2
N2 - 15 g / 28.02 g/mol = 0.54 mol N2
He - 10 g / 4.0 g/mol = 2.5 mol He
Add all the moles of gases.
0.78 + 0.54 + 2.5 = 3.82 moles
Divide O2 moles by total moles.
0.78/3.82 = 0.20
Answer:
250 minutes
Explanation:
60 seconds = 1 minute
15000 secods = 15000 / 60
1500 secons = 250 minutes
C. The design would not be cost-efficient; the plane would require more fuel due to increased thrust from higher drag.
