Chemistry
Assertion (A): Alkali metals do not form dipositive ions.
Reason (R): After loss of one electron alkali metals achieve stable electronic configuration of noble gases.
- Both A and R are true and R is the correct explanation of A
- Both A and 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
Reason — Alkali metals (such as lithium, sodium, and potassium) do not form dipositive ions. Instead, they form monovalent cations by losing one electron. This is because they have a single electron in their outermost shell, and losing this one electron achieves the stable noble gas configuration.
Related Questions
A nitrate which forms a precipitate with ammonium hydroxide and is also soluble in excess of it:
- ferrous nitrate
- ferric nitrate
- lead nitrate
- copper nitrate
Which of the following electronic configuration represents the most electropositive element?
- 2, 1
- 2, 8, 1
- 2, 2
- 2, 8, 2
The ratio between the volumes occupied by 4.4 grams of carbon dioxide and 2 grams of hydrogen gas is:
- 2.2 : 1
- 1 : 2.2
- 1 : 10
- 10 : 1
Aqueous lead (II) nitrate can be distinguished from aqueous zinc nitrate by adding any of the following solution in excess, except:
- aqueous potassium chloride
- aqueous sodium sulphate
- dilute sulphuric acid
- sodium hydroxide solution