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monitta
3 years ago
5

When does phenolphthalein turn pink?

Chemistry
2 answers:
lesya692 [45]3 years ago
5 0
A.) <span>Phenolphthalein is colorless in an acid, but it turns bright pink in the presence of a base.

Hope I helped you!!</span>
Svetach [21]3 years ago
3 0

Answer is: a) in the presence of a base.

Phenolphthalein is colorless in acidic solutions and pink in basic solutions.

Acid-base indicators are usually weak acids or bases and they are chemical detectors for hydrogen or hydronium cations.

Example for acid-base indicator is phenolphthalein (molecular formula C₂₀H₁₄O₄).

When solution turns phenolphthalein pink, it means it is basic (pH>7).

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Answer:

48.8%

Explanation:

The reaction has a 1:1 mole ratio so;

Number of moles of benzoic acid reacted = mass/molar mass = 3.8 g/122.12 g/mol = 0.03 moles

So;

0.03 moles of methyl benzoate is formed in the reaction

Mass of methyl benzoate formed = 0.03 moles * 136.15 g/mol = 4.1 g

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The chemical equation of magnesium and nitric acid
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The atomic radius is the distance between center of two bonded atoms.

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In this way Cl⁻ will have the largest atomic radii because one extra electron is added and its atomic number is already greater than fluorine.

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