The correct answer is: [B]: "produces OH⁻ ions" .
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→ { This is the answer choice that goes in the portion in the circle labeled, "x" ;
→ within the "Venn Diagram given [in this very question/problem.]} .
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Step-by-step explanation:
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Essentially, the question is asking:
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"Which of the following answer choices are characteristics of "bases", ONLY ? " ;
→ {and NOT TRUE of "acids", only} ; AND:
→ {and NOT TRUE of BOTH: "acids" ; AND: "bases"}? ;
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The answer choices, as posted, are:
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[A]: conducts electric current ;
[B]: produces OH⁻ ions .
[C]: tastes sour ;
[D]: reacts with carbonates.
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→ The correct answer is: [B]: "produces OH⁻ ions" .
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Note that "bases" (NOT "acids") produce "hydroxide ions" {i.e. "OH⁻ " ions} when dissolved in water; whereas "acids" (NOT "bases") produce "hydrogen ions" {i.e. " H⁺ " ions} when dissolved in water.
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Hence, this answer choice: [B]: "produces OH– ions" ;
→ is CORRECT.
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Let us consider the other answer choices:
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[A]: "conducts electric current" ; is INCORRECT. This characteristic applies to BOTH: "acids" (of various types) ; AND to "bases" (of various types) — and NOT strictly to "bases" .
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[C]: "tastes sour" ; is INCORRECT.
This characteristic applies to "acids"— AND NOT to "bases".
Note that "acids" tend to taste "sour", whereas as "bases" tend to taste "chalky".
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[D]: "reacts with carbonates" ; is INCORRECT.
Note that "acids" — NOT "bases" — react with carbonates ["carbonates" are "bases"] — to produce a salt and water— and release "CO₂ (g) " — that is, "carbon dioxide" (in gaseous form).
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→ The correct answer is:
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→ Answer choice: [B]: " produces OH⁻ ions " .
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Hope this answer—and rudimentary [yet lengthy] — explanation is of help to you.
Best wishes in your academic pursuits!
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