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3 years ago

What are pigments? How do they work?

Chemistry

2 answers:

Ivanshal [37]3 years ago

6 0

Explanation:

Most pigments work by absorbing certain wavelengths of light. Other wavelengths are reflected or scattered, which cause you to see those colours. At the atomic level, certain wavelengths of light are of the correct energy to excite specific transitions of electrons in the molecules or the solid.

neonofarm [45]3 years ago

3 0

Pigments are colors lol

You might be interested in

At-57 °C and 1 atm, carbon dioxide is in which phase? View Available Hint(s) Phase diagrams for water (Figure 1)and carbon dioxi

goblinko [34]

Answer:

Gas

Increase the pressure

Explanation:

Let's refer to the attached phase diagram for CO₂ (not to scale).

At -57 °C and 1 atm, carbon dioxide is in which phase?

If we look at the intersection between -57°C and 1 atm, we can see that CO₂ is in the gas phase.

At 10°C and 2 atm carbon dioxide is in the gas phase. From these conditions, how could the gaseous CO₂ be converted into liquid CO₂?

Since at 10°C and 2 atm carbon dioxide is below the triple point, the only way to convert it into liquid is by increasing the pressure (moving up in the vertical direction).

4 0

3 years ago

Which of the following is a combustion reaction?

azamat

Answer:

A.NaOH+HCI+NaCI+H2O

Explanation:

It's a Acid-base

5 0

3 years ago

Air pressure is lowest in the lungs during whi h of the following points during inspiration or expiration

AlladinOne [14]

Answer:

Inspiration

Explanation:

This question is on application of Boyle's law; pressure is inversely proportional to volume.when we inhale air, the diaphragm and the muscles in the ribs contract thus increasing the volume in the lungs.Increased volume of the lungs cause the pressure to decrease.During exhaling, the diaphragm and muscles in the ribs relax, making the lungs to recoil and reduce in volume to force air out.Pressure in the lungs is increased than that in the environment making air to move out.

4 0

3 years ago

In a reaction vessel, 17.6 g of solid chromium(III) oxide, Cr2O3, was allowed to react with excess carbon tetrachloride in the f

notsponge [240]

Answer:

72.53% is the yield of CrCl3

Explanation:

Given

Reaction:

Cr2O3(s) + 3 CCl4(l) → 2 CrCl3(s) + 3 COCl2(aq)

CCl4 is in excess and 17.6g Cr2O3 present

The reaction yields 26.6g of CrCl3

To Find:

% yields of the reaction

Also given

Molar mass of CrCl3 = 158.35g/mol

Molar mass of Cr2O3 = 152.00 g/mol

By the stoichiometry of the reaction

1 mole of Cr2O3 gives 2 moles of CrCl3

1 x1 52 g of Cr2O3 gives 2x 158.35 g of CrCl3

= 1 52 g of Cr2O3 gives 316.70 g of CrCl3

17.6 g of Cr2O3 gives (17.6÷152) × 316.70 g CrCl3

= 36.67 g CrCl3

but actual yield is only 26.6g

so % yield is (26.6 ÷÷ 36.67) × 100

= 72.53% is the yield of CrCl3

8 0

3 years ago

If 31.6 g of KMnO4 is dissolved in enough water to give 160 mL of solution, what is the molarity?

Zina [86]

Answer:

A. 1.25M

B. 19.98g

Explanation:

A. Data obtained from the question include the following:

Mass of KMnO4 = 31.6 g

Volume = 160 mL

Molarity =..?

We'll begin by calculating the number of mole KMnO4 in the solution. This is can be obtained as follow:

Mass of KMnO4 = 31.6 g

Molar mass of KMnO4 = 39 + 55 + (16x4) = 158g/mol

Number of mole of KMnO4 =..?

Mole = mass /Molar mass

Number of mole of KMnO4 = 31.6/158 = 0.2 mole

Now, we can obtain the molarity of the solution as follow:

Volume = 160 mL = 160/1000 = 0.16L

Mole of KMnO4 = 0.2 mole

Molarity = mole /Volume

Molarity = 0.2/0.16 = 1.25M

B. Data obtained from the question include the following:

Volume = 300mL

Molarity = 0.74 M

Mass of H2C2O4 =..?

First, we shall determine the number of mole H2C2O4. This is illustrated below:

Volume = 300mL = 300/1000 = 0.3L

Molarity = 0.74 M

Mole of H2C2O4 =?

Mole = Molarity x Volume

Mole of H2C2O4 = 0.74 x 0.3

Mole of H2C2O4 = 0.222 mole

Now, we can easily find the mass of H2C2O4 by converting 0.222 mole to grams as shown below:

Number of mole of H2C2O4 = 0.222 mole

Molar mass of H2C2O4 = (2x1) + (12x2) + (16x4) = 2 + 24 + 64 = 90g/mol

Mass of H2C2O4 =..?

Mass = mole x molar mass

Mass of H2C2O4 = 0.222 x 90

Mass of H2C2O4 = 19.98g

5 0

3 years ago