Chemistry
Assertion (A): A chemical equation must be balanced in order to follow the law of conservation of mass.
Reason (R): A chemical equation called as skeletal equation may not have equal number of atom of each element present in the reactants and products.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Answer
Both A and R are true and R is the correct explanation of A.
Explanation — According to the law of conservation of mass, the total mass of reactants equals the total mass of products. Therefore, the number of atoms of each element must be the same on both sides of a chemical equation, so the equation must be balanced. A skeletal equation is an unbalanced equation and may have unequal atoms of elements in reactants and products. Hence, balancing the equation is necessary, and R correctly explains A.
Related Questions
Assertion (A): A chemical reaction is a process which involves the transformation of one or more substances into new substances with entirely different properties.
Reason (R): Breaking of chemical bonds between the atoms of reacting susbtances takes place to form new bonds between the atoms forming new substances called as products.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Assertion (A): The reaction of an acid with a base to produce salt and water is called a neutralisation reaction.
Reason (R): Neutralisation reaction is a double displacement reaction.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Assertion (A): When a copper coil is dipped in an aqueous solution of silver nitrate, the colour of the solution slowly changes from colourless to blue.
Reason (R): Silver metal is more reactive than copper.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.