An ion with a charge of positive two, and the same electron configuration as the chloride ion, is the
A - VCE - SSCE Chemistry - Question 6 - 2002 - Paper 1
Question 6
An ion with a charge of positive two, and the same electron configuration as the chloride ion, is the
A. phosphide ion.
B. sulfide ion.
C. magnesium ion.
D. calcium ... show full transcript
Worked Solution & Example Answer:An ion with a charge of positive two, and the same electron configuration as the chloride ion, is the
A - VCE - SSCE Chemistry - Question 6 - 2002 - Paper 1
Step 1
Identify the Chloride Ion Configuration
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Answer
The chloride ion (Cl⁻) has an atomic number of 17 and thus an electron configuration of [Ne]3s23p6. This configuration corresponds to that of the nearest noble gas, Argon, which also has 18 electrons.
Step 2
Determine the Required Configuration
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Answer
An ion with a charge of positive two that has the same electron configuration as chloride must have lost two electrons. Thus, the neutral atom must have had 18 electrons initially, which corresponds to atomic number 18.
Step 3
Identify the Element
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Answer
The element with atomic number 18 is argon (Ar). The ions listed in the options must be analyzed to find an ion that has 18 electrons after losing 2.
Step 4
Evaluate the Options
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Answer
A. Phosphide ion (P³⁻) has 18 electrons (15 + 3).
B. Sulfide ion (S²⁻) has 18 electrons (16 + 2).
C. Magnesium ion (Mg²⁺) has 10 electrons (12 - 2).
D. Calcium ion (Ca²⁺) has 18 electrons (20 - 2).
From this analysis, both the
C. magnesium ion and D. calcium ion are close, but the calcium ion matches the configuration exactly after losing electrons.
Step 5
Conclusion
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Answer
The correct answer is D. calcium ion, as it has a charge of +2 and shares the same electron configuration as the chloride ion.
