18. Which one of the following is generally NOT true about elements in the same period?
A. Number of valence electrons of the elements remains the same.
B. Elements at the right side of the period are smaller in size
C. Elements at the right side of the period have higher electron affinity.
D. Elements at the right side of the period have high metallic character.

Statement B "Elements at the right side of the period are smaller in size" is not true.

Explanation:

Going through the rows of the elements in the period the size of the elements get continuously bigger.

answer:

the reaction is type of combination reaction.

explanation:

on the product side, there are 2 molecules of bonded to fe   which means one atom of fe are combined two molecules of . so, balanced chemical equation becomes :

this reaction follows the reaction type of combination reaction. a combination reaction is defined as chemical reaction in which reactants combines together to form a single product.