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2 years ago

How do I draw energy level diagrams?

1 answer:

7 0

Energy levels inside an atom are the specific energies that electrons can have when energy occupies specific orbitals. Electrons can be excited to higher energy levels by absorbing energy from the surroundings, an equivalent light is emitted when an electron returns from a high energy state to a lower one. Representation of this diagrammatic is known as the energy level diagram.

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I need to show work on all my problems and I am not God in math

Salsk061 [2.6K]

That's cool man, you should study more... wheres the question though?

6 0

3 years ago

What is a good indicator for titrating potassium hydroxide with hydrobromic acid?

Cerrena [4.2K]

Potassium hydroxide is a strong base and hydrobromic acid is a strong acid. This implies that the pH of the end-point [neutralization] of their titration will be around pH 7. A good indicator for this kind of pH is bromthymol blue. This is because this indicator changes its colour at pH 7.

4 0

3 years ago

How many grams of phosphorus are in a sample of Ca3(PO4)2 that contains 50.0 g of calcium? Answer: ________ grams of phosphorus.

wel

<u>Answer:</u> The mass of phosphorus that is present for given amount of calcium is 28.53 g.

<u>Explanation:</u>

We are given:

Mass of calcium = 50 grams

The chemical formula of calcium phosphate is $Ca_3(PO_4)_2$

Molar mass of calcium = 40 g/mol

Molar mass of phosphorus = 31 g/mol

In 1 mole of calcium phosphate, 120 grams of calcium is combining with 62 grams of phosphorus.

So, 50 grams of calcium will combine with = $\frac{62}{120}\times 50=28.53g$ of phosphorus.

Hence, the mass of phosphorus that is present for given amount of calcium is 28.53 g.

6 0

3 years ago

The pKa of chloroacetic acid is 2.9. If an organic chemist has a 0.10 M aqueous solution of chloroacetic acid at pH 2.4, what pe

Trava [24]

Answer:

The answer is given below.

Explanation:

We will consider the acid as HA and will set up an ICE table with the equilibrium dissociation of α.

AT pH 2.4 the initial H+ concentration will be 3.98^10-3 M

HA → H+ + A-

Initial concentration: 0.1 → 3.98 ^10-3 + 0

equilibrium concentration: 0.1(1-α) → 3.98 * 10-3 + 0.1α 0.1α

pKa of chloroacetic acid is 2.9

-log(Ka) = 2.9

Ka = 1.26 * 10-3

From the equation, Ka = [H+] * [A-] / [HA]

1.26 * 10-3 = (3.98 * 10-3 + 0.1α )* 0.1α / 0.1(1-α)

Since α<<1, we assume 1-α = 1

Solving the equation, we have: α = 0.094

Since this is the fraction of acid that has dissociated, we can say that % of base form = 100 * α= 9.4%

6 0

3 years ago

What is the ph of a solution labeled .30 trimethylamine k for trimethylamine is 7.42 x 10^4

valentina_108 [34]

Answer:the pH is 12

Explanation:

First We need to understand the structure of trimethylamine

Due to the grades of the bond in the nitrogen with a hybridization sp3 is 108° approximately, then is generated a dipole magnetic at the upper side of the nitrogen, this dipole magnetic going to attract a hydrogen molecule of the water making the water more alkaline

C3H9N+ H2O --> C3H9NH + OH-

$k=\frac{[C3H9NH]*[OH-]}{[C3H9N]}$

Then:

The concentration of the trimethylamine is 0.3 and the concentration of the ion C3H9NH is equal to the OH- relying on the stoichiometric equation. We could find the concentration of the OH- ion with the square root of the multiplication between k and the concentration of trimethylamine

[OH-]= $\sqrt{ 0.3*7.42x10^{-4}}$

[OH-]=0.01

pH=14-(-log[OH-])

pH=12

5 0

3 years ago