Chemistry
Assertion (A): The atomic mass of sodium is 23 amu.
Reason (R): An atom of sodium is 23 times heavier than an atom of carbon with mass 12 amu.
- 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
A is true but R is false.
Explanation — The atomic mass of sodium is 23 amu. Hence, the assertion (A) is true.
An atom of sodium is 23 times heavier than one-twelfth the mass of a carbon-12 atom, not 23 times heavier than an atom of carbon with mass 12 amu. Hence, reason (R) is false.
Related Questions
Calculate percentage of platinum in [(NH4)2 PtCl6]. Ammonium chloride platinate in nearest whole number.
Calculate percentage composition of the elements in calcium phosphate Ca3(PO4)2.
Assertion (A): An atom is the smallest part of matter which can take part in a chemical reaction.
Reason (R): Atoms of every element can exist independently.
- 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): All equations need to be balanced.
Reason (R): An unbalanced equation would imply that atoms have been created or destroyed.
- 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.