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4 years ago

Determine whether each chemical substance would remain the same color or turn pink in the presence of phenolphthalein.

Chemistry

1 answer:

Serhud [2]4 years ago

3 0

Answer:

See the answer below

Explanation:

The complete question can be seen in the attached image.

Phenolphthalein is an indicator that is often utilized in an acid-base reaction to indicate the endpoints of such reactions due to its ability to change color from pink/colorless to colorless/pink depending on if the final solution is acidic or basic.

Phenolphthalein is usually colorless in acidic solutions and appears pink in basic solutions. The more basic or alkaline a solution is, the stronger the pink color of phenolphthalein. Hence;

1. Ammonia with a pH of 11 is basic, phenolphthalein will turn pink.

2. Battery acid with a pH of 1 is acidic, it will remain colorless.

3. Lime juice with a pH of 2 is acidic, it will remain colorless.

4. Mashed avocado with a pH of 6.5 is acidic, it will remain colorless.

5. Seawater with a pH of 8.5 is basic, it will turn pink.

6. Tap water with a pH of 7 is neutral, it will remain colorless

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Fill in the blank: After a chemical reaction, the atoms of the reactant _____ to form new products.

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The atoms of the reactant rearrange to form new products.

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3 years ago

Two compounds are standing at the same temperature. Compound "A" is evaporating more slowly than compound "B." According to the

frosja888 [35]

Answer:

Option D) Compound B may have a lower molecular weight.

Explanation:

Compound A and B are standing at the same temperature yet compound A is evaporating more slowly than compound B.

This simply indicates that compound B have a lower molecular weight than compound A.

This can further be seen when gasoline and kerosene are placed under same temperature. The gasoline will evaporate faster than kerosene because the molecular weight of the gasoline is low when compared to that of the kerosene.

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3 years ago

The synthesis of ATP by oxidative phosphorylation, using the energy released by movement of protons across the membrane down the

AlexFokin [52]

Answer:

It is an example of coupling an exogenic reaction to an endogenic reaction.

Explanation:

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3 years ago

When a diprotic acid, , is titrated with , the protons on the diprotic acid are generally removed one at a time, resulting in a

marshall27 [118]

Answer:

At the second equivalent point 200 mL of NaOH is required.

Explanation:

at the first equivalent point:

H2A + OH- = HA- + H2O

initial mmoles y*100 y*100 - -

final mmoles 0 0 y*100 y*100

at the second equivalent point:

HA- + OH- = A2- + H2O

initial mmoles y*100 y*100 - -

final mmoles - - y*100 y*100

at the second equivalent point we have that y*100 mmoles of NaOH or 100 mL of NaOH ir required, thus:

at the second equivalent point 200 mL of NaOH is required.

4 0

4 years ago

Calculate the Kelvin temperature to which 10.0 L of a gas at 27 °C would have to be heated to change the volume to 12.0 L. Units

KatRina [158]

Hello!

For this problem, we will be applying Charles' Law:

V1/T1 = V2/T2

Now that we have the formula, let's convert the temperature to Kelvin.

27 + 273 = 300K

Let's plug everything in now!

10/300 = 12.0/x

Simplified:

1/30 = 12.0/x

Cross-multiply:

1x = 30*12.0

x = 360

Check!

10/300 = 12/360

300*12 = 360*10

3600 = 3600

Therefore, you would have to heat the gas at a temperature of 360K in order to raise the volume to 12.0L.

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3 years ago