C6H12O6, MgCL2, NaCl are compounds
Pb is element
O2 is neither compound nor element, it's a molecule. But if must need to categorize it, then you can consider it in element, but remember it's not an element
Answer:
An organic chemical compound consisting solely of hydrogen and carbon atoms is a hydrocarbon. Hydrocarbons are compounds that occur naturally and form the basis of crude oil , natural gas, coal and other significant sources of energy.
I can’t see the picture here’s what I see
Remark
The given thing on the right is a positron. The mass for these subatomic particles is considered to be 0. It's atomic number is 1 which means it is a blood relative of a proton.
So essentially what happens is that X is one space to the left on the periodic table. But let's solve this a little bit more formally.
Solution

y stays the same at 147. It is z that changes.
65 = z + 1 Subtract 1 from both sides.
64 = z
So the chemical with 64 as its position on the periodic table is
Gadolinium and the answer is C
Answer: It is Mole.
Explanation:
Mole is the SI unit of measurement used to measure the number of things, usually atoms or molecules. One mole of something is equal to 6.02214078×1023 of same things (Avogadro's number).