Chemistry
Assertion (A): Noble gases do not combine with other elements.
Reason (R): The outermost orbit of noble gases are complete, they have a stable electronic configuration.
- 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 — Noble Gases or Inert gases are Group 18 elements. They do not react with other elements because they have complete 8 electrons in their outermost orbits (except He, which has only 2), which is stable electronic configuration. Hence both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
Related Questions
Which of the following groups of modern periodic table has elements in all the three states i.e., solid, liquid, gas?
P — Group 18
Q — Group 17
R — Group 16
- Only P
- Only Q
- Only R
- Both Q and R
Modern periodic table is used to predict:
P — Whether an element is solid, liquid or gas.
Q — The nature of chemical bonds formed when elements combine.
R — The formula of the compound formed when elements combine.
- Only P
- Only Q
- Only R
- Both Q and R
Assertion (A): Lithium, sodium and potassium form a Dobereiner's triad.
Reason (R): The atomic mass of the middle element is the average of the masses of the other two elements.
- 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): Chlorine with atomic number 17 is placed in group 17 and period 3.
Reason (R): The number of shells signifies a period, while the number of valence electrons indicates the group.
- 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.