Question

Which of the following is a chemical equation that accurately represents what happens when sulfur and oxygen are produced from sulfur trioxide? A. 2S + 3O2 --> 2SO3 B. 2SO3 --> 2S + 3O2 C. S + O2 --> SO3 D. SO3 --> S + O2

Answer 1

The correct formation reaction of sulfur and oxygen from sulfur trioxide is $\boxed{2{\text{S}}{{\text{O}}_3} \to 2{\text{S}} + 3{{\text{O}}_{\text{2}}}}$.

Further explanation:

The chemical reaction that contains an equal number of atoms of the different elements in the reactant as well as in the product side is known as a balanced chemical reaction. The chemical equation is required to be balanced to follow the Law of the conservation of mass.

The five types of chemical reactions are as follows:

1. Combination reactions:

These reactions are also known as a synthesis reaction. These are the reaction in which two or more reactants combine to form a single product. These are generally accompanied by the release of heat so they are exothermic reactions.

Example of combination reaction:

 ${\text{Ba}} + {{\text{F}}_2} \to {\text{Ba}}{{\text{F}}_2}$

2. Decomposition reactions:

The opposite of combination reactions is called a decomposition reaction. Here, a single reactant gets broken into two or more products. Such reactions are usually endothermic because energy is required to break the existing bonds between the reactant molecules.

Example of decomposition reaction:

 $2{{\text{H}}_2}{{\text{O}}_2} \to 2{{\text{H}}_2}{\text{O}} + {{\text{O}}_2}$

3. Displacement reactions

Also known as replacement or metathesis reactions. Here, one of the reactants gets replaced by the other one. Generally, the more reactive element displaces the less reactive element. Both metals and non-metals can take part in displacement reactions.

Example of displacement reaction:

${\text{Cu}} + {\text{AgN}}{{\text{O}}_3} \to {\text{Ag}} + {\text{Cu}}{\left( {{\text{N}}{{\text{O}}_3}} \right)_2}$

4. Double displacement reactions

It is defined as the reaction in which ions of two compounds interchange with each other to form the product. A general double displacement reaction between two compounds AX and BY can be written as follows:

${\text{AX}} + {\text{BY}} \to {\text{AY}} + {\text{BX}}$  

Example of double displacement reaction:

 ${\text{N}}{{\text{a}}_2}{\text{S}} + {\text{HCl}} \to {\text{NaCl}} + {{\text{H}}_2}{\text{S}}$

5. Combustion reactions:

These are the reactions that take place when hydrocarbons are burnt in the presence of oxygen to form carbon dioxide and water. These are also referred to as burning.

A. $2{\text{S}} + 3{{\text{O}}_2} \to 2{\text{S}}{{\text{O}}_3}$  

Here, sulfur and oxygen react with each other to form sulfur trioxide. The number of sulfur atoms on the reactant and product side is 2 while that of oxygen on both sides is 6. The reaction is balanced but sulfur trioxide is formed in this reaction, not sulfur and oxygen. So this is incorrect.

B. $2{\text{S}}{{\text{O}}_3} \to 2{\text{S}} + 3{{\text{O}}_{\text{2}}}$  

Here two moles of sulfur trioxide are decomposed to form two moles of sulfur and three moles of oxygen. The number of sulfur atoms on the reactant and product side is 2 while that of oxygen on both sides is 6. The reaction is balanced and therefore this is correct.

C. ${\text{S}} + {{\text{O}}_2} \to {\text{S}}{{\text{O}}_3}$

Here sulfur and oxygen react with each other to form sulfur trioxide. The numbers of sulfur atoms on reactant and product sides are 1 and 2 respectively while those of oxygen on both sides are 2 and 3 respectively. The reaction is not balanced and this shows the formation of sulfur trioxide, not sulfur and oxygen. So this is incorrect.

D. ${\text{S}}{{\text{O}}_3} \to {\text{S}} + {{\text{O}}_2}$

Here one mole of sulfur trioxide is decomposed to form one mole of sulfur and one mole of oxygen. The number of sulfur atoms on both the reactant and product side is 1 while those of oxygen on both sides are 3 and 2 respectively. The reaction is not balanced. So this is incorrect.

Learn more:

1. Balanced chemical equation: brainly.com/question/1405182

2. Identify the precipitate in the reaction: brainly.com/question/8896163

Answer details:

Grade: High School

Subject: Chemistry

Chapter: Chemical reaction and equation

Keywords: balanced chemical reaction, correct, incorrect, sulfur, oxygen, 3, 2, 1, 6, S, O2, SO3.

Answer 2

S + O₂  → SO₃

This can be balanced by:

2S + 3O₂  → 2SO₃

Option A.

If we check:  Left Hand Side (LHS), Right Hand Side (RHS)

For Sulphur:

                       LHS                RHS
S                      2                    2
O                    3*2 = 6            2*3 = 6