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1 year ago

Which statements are true about light waves? (Select all that apply.)

Chemistry

1 answer:

Diano4ka-milaya [45]1 year ago

4 0

Answer:

A C D I believe

Explanation:

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Need help asap! A 200 L balloon is blown up inside at 100 K. It is then taken outside in the hot sun and heated to 400K. What is

liq [111]

<h2>Answer</h2>

The volume will be<u> 50 L</u>

<h2>Explanation</h2>

From Kelvin Law of Temperature, we know that

$V_{1} T_{1} =V_{2} T_{2}$

We know that

$V_{1}$ = 200 L

$T_1$ = 100 K

$T_2$ = 400 K

So,

$V_{2} = V_{1} T_{1}/T_{2}$

$V_{2} = 200*100/400$

$V_{2} = 50 L$

The answer of the givern question is 50L

5 0

2 years ago

Read 2 more answers

As a technician in a large pharmaceutical research firm, you need to produce 250. mL of a potassium dihydrogen phosphate buffer

Reika [66]

Answer:

We will need 147.772 mL of KH2PO4 to make this solution

Explanation:

For this case we can give the following equation:

H2PO4 - ⇄ H+ + HPO42-

With following pH- equation:

pH = pKa + log [HPO42-]/[H2PO4-]

7.05 = 7.21 + log [HPO42-]/[H2PO4-]

-0.16 = log [HPO42-]/[H2PO4-]

10^-0.16 = [HPO42-]/[H2PO4-]

0.6918 = [HPO42-]/[H2PO4-]

Let's say the volume of HPO42-= x then the volume of H2PO4- will be 250 mL - x

Since both have a concentration of 1M = 1 mol /L

If we plug this in the equation 0.6918 = [HPO42-]/[H2PO4-]

0.6918 = x / (250 - x)

0.6918*250 - 0.6918x = x

172.95 = 1.6918x

x = 102.228 mL

The volume of HPO42- = 102.228 mL

Then the volume of H2PO4- = 250 - 102.228 = 147.772 mL

To control this we can plug this in the pH equation

7.05 = 7.21 + log [HPO42-]/[H2PO4-]

7.05= 7.21 + log (102.228 / 147.772) = 7.05

We will need 147.772 mL of KH2PO4 to make this solution

3 0

2 years ago

A salt shaker filled with 17.0g sodium chloride contain how many moles?

kati45 [8]

The molecular formula for sodium chloride is NaCl. The sum of their atomic weights is (22.99 grams/mole + 35.45 grams/mole) = 58.44 grams/mole
take (17.0 grams)/(58.44 grams/mole), which equals 0.291 moles of NaCl.

8 0

2 years ago

The half-life of radium-226 is 1,600 years. It decays into radon-222. What fraction of the original amount of radium-226 in a sa

Mnenie [13.5K]

Answer:

Your answer will be C. 1/32

6 0

2 years ago

Read 2 more answers

The electronic configuration of an element is given below.

Shalnov [3]

Answer:

It is reactive because it has to gain an electron to have a full outermost energy level.

Explanation:

The electron configuration of oxygen is 1s2,2s2 2p4.

Oxygen is in group six in the periodic table so it has six electrons in its valence shell. This means that it needs to gain two electrons to obey the octet rule and have a full outer shell of electrons (eight).

3 0

1 year ago