Answer:
A) 
Explanation:
m = Mass of water = 38.9
M = Molar mass of water = 18 g/mol
= Avogadro's number = 
The reaction of electrolysis would be
Number of moles of 
From the reaction it can be seen that 2 moles of gives 1 mole of 
So, number of moles of produced is
Number of molecules
So, of oxygen is produced.
Answer:
HCL
Explanation:
Covalent bond are formed between non metals so look for the pair of non metal atoms and this would be hydrogen chloride (HCL)
Answer:
Isotopes are variants of an element, where the number of neutrons is different but its number of protons stay the same.
Explanation:
If the number of protons had changed then it would just be a different element.
Electron number changing simply adds charge to the atom, and doesn't change it or anything.
PLS GIVE BRAINLIEST
