Answer:
Option A - nucleus
Explanation:
A molecule is formed when two or more atoms join together chemically. If atoms combine that are of two or more different elements, we call that a compound. All compounds are molecules, but not all molecules are compounds.
Answer:
B
Explanation:
placenta comes after baby
A qualitative test for sulfate in alum crystals using ionic reactions of barium chloride (BaCl2) is given Ba²⁺(aq) + SO₄²⁻ (aq) → BaSO₄(s).
<h3>What is qualitative test?</h3>
Qualitative test measures changes in color, melting point, odor, reactivity, radioactivity, boiling point, bubble production, and precipitation of the sample.
<h3>Qualitative test for sulfate in alum crystals </h3>
When an aqueous solution of a barium salt (BaCl₂) is mixed with an aqueous solution containing sulfate, a white precipitate of insoluble BaSO₄ forms according to the net ionic equation given below;
Ba²⁺(aq) + SO₄²⁻ (aq) → BaSO₄(s)
Thus, a qualitative test for sulfate in alum crystals using ionic reactions of barium chloride (BaCl2) is given Ba²⁺(aq) + SO₄²⁻ (aq) → BaSO₄(s).
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