The table shows the total number of electrons in atom a and atom b. atom number of electrons a 10 b 18 which statement is correct? a will give up electrons to form bonds. b will give up electrons to form bonds. both a and b will be chemically unreactive. both a and b will gain electrons to become stable.

Both A and B will be unreactive!

Explanation:

10=2, 8

18=2, 8, 8

Option (c) is the correct answer.

Explanation:

It is given that atom A contains 10 electrons so, its electronic distribution is 2, 8. Whereas atom B contains 18 electrons so, its electronic distribution is 2, 8, 8.

Since, both these atoms have completely filled octet so they do not need to react with any other element in order to attain stability.

Therefore, both these elements are unreactive in nature.

Thus, we can conclude that both A and B will be chemically unreactive.

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g