The
reaction is<span>
C</span>₂H₄ +
O₂ → CO₂ + H₂O<span>
To balance the equation, both side have same
number of elements. Here,</span>
In left hand
side has
in right hand side has
4 H atoms
2 H
atoms
2 C atoms 1 C
atom
<span>
2 O atoms 3 O
atoms
First, we have to balance number of C atoms and number of H atoms in both side.
To balance C atoms, '2' should be added before CO</span>₂ and to balance H atoms, '2' should be added
before H₂<span>O.
Then number of oxygen atoms is </span>2 x 2 + 2 = 6 in right hand side. So, 3 should be
added before O₂<span> in left hand side.
After balancing the equation should be,</span>
C₂H₄<span> + 3O</span>₂<span> → 2CO</span>₂<span> + 2H</span>₂O
He could be blindfolded and know which was his and which was his sister's. All he would need to do is pick them both up and if they were too big then pick them up one at a time. The lumber might make it harder to tell, but this is a question about physical properties.
So there is a change in mass which for the purpose of this question should be quite different. His sister's ought to be much lighter than his. He would find it easier to pick up.
0.000735 in scientific notation is 7.35 x 10^-4
Fluorine! It's highly reactive, since it has 7 electrons and wants an extra electron to fill its valence shell.
