Polyethylene is a type of plastic.
Answer:
0.641 moles of ethane
Explanation:
Based on the equation:
C2H6(g) + 7/2O2(g) → 2CO2(g) + 3H2O(l)
We can determine ΔH of reaction using Hess's law. For this equation:
<em>Hess's law: ΔH products - ΔH reactants</em>
ΔH = {2ΔHCO2 + 3ΔHH2O} - {ΔHC2H6}
<em>Pure monoatomic substances have a ΔH = 0kJ/mol; ΔHO2 = 0kJ/mol</em>
<em />
ΔH = {2*-393.5kJ/mol + 3*-285.8kJ/mol} - {-84.7kJ/mol}
ΔH = -1559.7kJ/mol
That means when 1 mole of ethane is in combustion there are released 1559.7kJ of heat. To produce 1.00x10³kJ there are needed:
1.00x10³kJ * (1mole ethane / 1559.7kJ) =
<h3>0.641 moles of ethane</h3>
Answer:
Most of the food energy that enters a trophic level is "lost" as heat when it is used by organisms to power the normal activities of life. Thus, the higher the trophic level on the pyramid, the lower the amount of available energy.
Explanation:
<u>The </u><u>emperical formula </u><u>can be </u><u>calculated </u><u>as follows:</u>
<u>mass :</u> 4.12g of N and 0.88g of H
<u>moles:</u> 4.12g/14.007 and 0.88g/1.008
<u>moles:</u> 0.294 and 0.873
<u>moles/smallest number</u>: (gives the ratio of atoms)
0.294/0.294 and 0.873/0.294
1 and 2.969
1 and 3
The simplest ratio of N : H is 1 : 3
<u>Hence the </u><u>emperical formula </u><u>is </u><u>NH3</u>
<u>Explanation:</u>
1. The emperical formula can be found by getting the <u>simplest ratio of atoms in a molecule.</u>
2. To get the simplest ratio of atoms we find out the <u>number of moles of each atoms in it.</u>
3. From the number of moles of atoms we can find the simplest ratio of each atom by dividing the <u>number of moles by the smallest number.</u>