Ethylene- C2H4 = 85.7% Carbon and 14.3% Hydrogen
Find the atomic masses for each element and multiply it by the number of atoms in the compound, then add.
C- 12.0 * 2= 24.0
H- 1.00 * 4= 4.00
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28.0
Take the masses for each element and divide it by the total mass. Then change the answer to get the percent.
C 24.0 / 28.0= .857 = 85.7%
H 4.00 / 28.0= .143 = 14.3%
<h3>
Ethylene is 85.7% Carbon and 14.3% Hydrogen </h3>
Answer:

Explanation:
Hello,
In this case, it is convenient to compute the car's mileage in km/L as follows:

In such a way, since the distance is measured to be 250 km, the volume requirement is:

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Answer:
Li and H
Explanation:
2Li(s)+2H2O(i)→2LiOH(aq)+H2(g) is full balanced