Models in science help you get the idea of what something looks like that's why your teacher may ask you to draw a diagram to help you remember what the object looks like.
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Answer:
C
Explanation
On the reactants side there is 4 Hydrogen atoms in total and two oxygen atoms on the left however on the right there is two hydrogen atoms and one oxygen atom. Leaving this equation unbalanced
Combustion equation of n-hexane:
2C₆H₁₄ + 19O₂ → 12CO₂ + 14H₂O
a)
Assuming we have 100 moles of air,
Oxygen = 20.9 moles
n-hexane required = 20.9/19 x 2
= 2.2 moles
LFL = Half of stoichometric amount = 2.2 / 2 = 1.1
LFL n-hexane = 1.1%
b)
1.1 volume percent required for LFL
1.1% x 1
= 0.0011 m³ of n-hexane required
