Chapter 7, Problem 7STP

Interpretation Introduction

Interpretation: The equation that best describes the reaction of element X ( $\text{Δ}$ ) with element Y ( ${\rm O}$ ) in the given diagram should be determined.

Concept Introduction: Chemical equation is written in such a way that the symbolic representation of reaction represents the reaction taking place in the system. The reactants are written on the left-hand side and the products are written on the right-hand side of the equation and are separated by an arrow, two or more reactants and products are separated by “+”.

The reactions for those the number of atoms of each element in the reactant and in the product, side are equal, such reactions are said to be a balanced chemical equation.

Answer to Problem 7STP

The correct option is (c), $\text{X + 2Y }\to {\text{ XY}}_{\text{2}}$ .

Explanation of Solution

Given:

  

In the given reaction, the $\text{Δ}$ represents element X and ${\rm O}$ represents element Y. The box on the left-hand side represents reactants and box on the right-hand side represents products.

Counting the number of elements in the reactant side:

  $\begin{array}{l}\text{Δ = 2}\\ {\rm O}\text{ = 8}\end{array}$

That means there are 2 elements of X and 8 elements of Y in the reactant side.

Now, counting the number of products and elements in the product side:

  ${\rm O}\text{ = 8}$

  

That means there are 2 element Y and 3compounds ${\text{XY}}_{\text{2}}$ in the product side.

It can be observed from the reaction that 1 atom of X combines with 2 atoms of Y to form a molecule ${\text{XY}}_{\text{2}}$ .

Hence, the chemical equation that best describes the reaction is:

  $\text{X + 2Y }\to {\text{ XY}}_{\text{2}}$