A) Mass Number
B) Protons and Electrons
C) (I think group but I'm not 100% sure on this...)
D) 12 (To work out the number of neutrons you do MASS number - ATOMIC number aka the number of protons so in this case you'd do 23-11=12)
Hope this helps
Answer:

Explanation:
Hello!
In this case, according to the given chemical reaction, it is possible to calculate the enthalpy change of the reaction via:

Since the enthalpy of formation of oxygen is 0. Thus, given the enthalpies of formation of gaseous carbon dioxide and water, we obtain:

Best regards!
Answer:
Number 1. The effective nuclear change of oxygen is greater that of fluorine.