Chemistry
Assertion (A): A chemical equation is written to represent molecules.
Reason (R): This is necessary for the law of conservation of mass
- 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 but R is not the correct explanation of A.
Explanation — A chemical equation represents molecules and it is necessary for the chemical equation to follow the law of conservation of mass. Hence, both assertion (A) and reason (R) are true.
However, balancing the equation is what ensures the law of conservation of mass. Therefore, reason (R) is not the correct explanation of assertion (A).
Related Questions
Assertion (A): In a chemical reaction, the total mass of the products remains the same as that of the reactants.
Reason (R): A chemical reaction involves a simple exchange of partners and no new species are formed.
- 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): Magnesium phosphate is written as Mg3(PO4)2.
Reason (R): The valencies of magnesium and phosphate are three and two respectively.
- 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): Chemical combination always takes place between two elements.
Reason (R): A single substance is formed in a chemical combination.
- 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): Hydroxyl radicals (OH•) are considered the "detergents" of the atmosphere.
Reason (R): Hydroxyl radicals are highly reactive and oxidise many pollutants, breaking them down into less harmful substances.
- 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.