Question

When a chemical reaction takes place, the number of atoms each element in the reactants ____ the number of atoms of each element in the products

Answer 1

Answer : When a chemical reaction takes place, the number of atoms each element in the reactants must be equal to the number of atoms of each element in the products.

Explanation :

Balanced chemical reaction : It is defined as the number of atoms of individual elements present on reactant side must be equal to the product side.

The reactants and products are separated by the right arrow.

The species present on the left side of the right arrow is the reactant and the species present on the right side of the right arrow is the product.

For example :

The unbalanced chemical reaction is,

`3CO(g)+Fe_2O_3(s)\rightarrow Fe(s)+3CO_2(g)`

This chemical reaction is an unbalanced reaction because in this reaction, the number of atoms of iron are not balanced while all the atoms are balanced.

In order to balanced the chemical reaction, the coefficient 2 is put before the 'Fe'.

Thus, the balanced chemical reaction will be,

`3CO(g)+Fe_2O_3(s)\rightarrow 2Fe(s)+3CO_2(g)`

Answer 2

Answer: is equal to

Step-by-step explanation: According to law of conservation of mass, the mass can neither be created nor be destroyed. Thus the mass of products must be equal to the mass of reactants.

In order to have same mass on both sides of the chemical equation, the number of atoms of each element must be same in reactants as well as products.

`2Na+Cl_2\rightarrow 2NaCl`