I'm not sure, but maybe burning point...
Answer:
The gain in mass by the negative electrode is the same as the loss in mass by the positive electrode. So the copper deposited on the negative electrode must be the same copper ions that are lost from the positive electrode.
Answer:
I believe the answer would be A, remain 5g because heating the balloon would increase the speed of the gas molecules, but not necessarily change the amount
1 molecule of C3H7O has 7 atoms of hydrogen (remember that the numbers to the right of each symbol ara subscripts and they indicate the number of atoms of that element in the molecular formula).
Then 5 molecules will have 5 * 7 atoms of hydrogen.
5 * 7 = 35.
Then the answer is that there are 35 atoms of hydrogen in 5 molecules of isopropyl alcohol, C3H7O
