I would say none because thats the only one that makes any sence.
Answer: Synthesis/ Combination
reaction
4 Al + 3S2 => 2 Al2S3
Explanation: The equation is now balanced the amount of each individual atom in both the reactant and product sides are equal.
NH3 has 1 Nitrogen atom and 3 hydrogen atoms.
Answer: Option (b) is the correct answer.
Explanation:
It is known that metals are the species which readily lose an electron and tend to attain a positive charge.
For example, atomic number of sodium is 11 and its is an alkali metal. It electronic distribution is 2, 8, 1.
And, in order to attain stability it readily loses an electron and thus it become
ion.
Also, it is known that species which tend to transfer or donate their valence electrons to other atoms tend to form ionic bond and the compound formed is known as ionic compound.
Therefore, we can conclude that the statement metal atoms held together by ionic bonds best describes a metal solid.