Which hydrocarbon pair below have identical mass percentage of C?
A: C3H4 and C3H6
B: C2H4 and C3H4
C: C2H4 and C4H2
D: C2H4 and C3H6
E: None of the above
My answer is E...Can any one help me?
should be D: C2H4 and C3H6
both give you the ratio 1:2
A trick to solving this type of problem is to reduce all of the ratios to either their simplest form or a percentage.
Ex. 3C/6H => 2C/4H => 1C/2H = 50% C
1/2 is the simplest form, and the molecule is 50% Carbon.
With this in mind, you should look over your options once more.
I think you are correct. To have the identical mass percentage of C the "other" compound must have a multiple of C with the same multiple of H and none of the answers qualify.
all of above is wrong.
i have the same question for school.
Amanda is right.
C2H4. %C = 24/28 = 85.714%
C3H6. %C = 36/42 = 85.714%
Of course, I can help you! But don't worry, I won't be doing any carbon copy answers here. Let's take a closer look at each pair and see which one has identical mass percentages of carbon.
A: C3H4 and C3H6 - These compounds have different numbers of hydrogen atoms, so their mass percentages of carbon would not be the same. Carbon is neither a show-off nor a shrinking violet, so it wants its percentage to be consistent.
B: C2H4 and C3H4 - These compounds have the same number of carbon atoms but different numbers of hydrogen atoms. So, the mass percentages of carbon in these two compounds would also be different. It's like comparing a tandem bike to a unicycle - they may both have wheels, but the number of riders is different.
C: C2H4 and C4H2 - Once again, we have the same number of carbon atoms, but this time, the number of hydrogen atoms is different. So, the answer is not C. These compounds are like mismatched socks - they might share some similarities, but they don't match up.
D: C2H4 and C3H6 - Finally, we have a pair where both the number of carbon atoms and hydrogen atoms differ. So, the mass percentages of carbon in these compounds would not be identical. It's like trying to find a twin when you're an only child - it's just not going to happen.
So, it looks like the answer is indeed E, none of the above. None of the pairs listed have identical mass percentages of carbon. Keep hunting for the right one, you're almost there!
Certainly! To determine which hydrocarbon pair has an identical mass percentage of carbon (C), we need to calculate the mass percentage of carbon for each pair. The mass percentage of an element is calculated as the mass of the element divided by the total mass of the compound, multiplied by 100.
Let's calculate the mass percentage of carbon for each pair:
A: C3H4
To calculate the mass percentage of carbon, we need to know the molar mass of C3H4. Carbon (C) has a molar mass of 12.01 g/mol, and hydrogen (H) has a molar mass of 1.01 g/mol.
Molar mass of C3H4:
(3 × 12.01 g/mol) + (4 × 1.01 g/mol) = 36.03 g/mol + 4.04 g/mol = 40.07 g/mol
Mass percentage of C in C3H4:
(3 × 12.01 g/mol) / 40.07 g/mol × 100% = 89.74%
A: C3H6
Molar mass of C3H6:
(3 × 12.01 g/mol) + (6 × 1.01 g/mol) = 36.03 g/mol + 6.06 g/mol = 42.09 g/mol
Mass percentage of C in C3H6:
(3 × 12.01 g/mol) / 42.09 g/mol × 100% = 85.73%
B: C2H4
Molar mass of C2H4:
(2 × 12.01 g/mol) + (4 × 1.01 g/mol) = 24.02 g/mol + 4.04 g/mol = 28.06 g/mol
Mass percentage of C in C2H4:
(2 × 12.01 g/mol) / 28.06 g/mol × 100% = 85.67%
C: C2H4
Molar mass of C4H2:
(4 × 12.01 g/mol) + (2 × 1.01 g/mol) = 48.04 g/mol + 2.02 g/mol = 50.06 g/mol
Mass percentage of C in C4H2:
(4 × 12.01 g/mol) / 50.06 g/mol × 100% = 95.60%
D: C2H4
Molar mass of C3H6:
(3 × 12.01 g/mol) + (6 × 1.01 g/mol) = 36.03 g/mol + 6.06 g/mol = 42.09 g/mol
Mass percentage of C in C3H6:
(2 × 12.01 g/mol) / 42.09 g/mol × 100% = 85.73%
From the calculations above, we can see that the mass percentage of carbon does not match for any of the hydrocarbon pairs. Therefore, the correct answer is E: None of the above.