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3 years ago

Select all answers that apply.

Chemistry

2 answers:

Sphinxa [80]3 years ago

5 0

The answers are B and C, glad to help

Viktor [21]3 years ago

3 0

I would have to say B and C, because they both give a time frame. But then again maybe A as well.

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In Nuclear chemistry, the key requirement for a chain reaction is that...a. each event must produce more than one particle capab

ahrayia [7]

Cccccccccccccccccccccccc

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3 years ago

Calculate the percent ionization of nitrous acid in a solution that is 0.249 M in nitrous acid. The acid dissociation constant o

sattari [20]

Answer:

4.26 %

Explanation:

There is some info missing. I think this is the original question.

Calculate the percent ionization of nitrous acid in a solution that is 0.249 M in nitrous acid. The acid dissociation constant of nitrous acid is 4.50 × 10 ⁻⁴.

Step 1: Given data

Initial concentration of the acid (Ca): 0.249 M

Acid dissociation constant (Ka): 4.50 × 10 ⁻⁴

Step 2: Write the ionization reaction for nitrous acid

HNO₂(aq) ⇒ H⁺(aq) + NO₂⁻(aq)

Step 3: Calculate the concentration of nitrite in the equilibrium ([A⁻])

We will use the following expression.

$[A^{-} ] = \sqrt{Ca \times Ka } = \sqrt{0.249 \times 4.50 \times 10^{-4} } = 0.0106 M$

Step 4: Calculate the percent ionization of nitrous acid

We will use the following expression.

$\alpha = \frac{[A^{-} ]}{[HA]} \times 100\% = \frac{0.0106M}{0.249} \times 100\% = 4.26\%$

4 0

4 years ago

How many molecules are present in the following quantity 0.250 mole of H2O

klio [65]

If 1mole ------------- is ---------------- 6.02*10²³
than 0.25mole ----- is ---------------- x

x = [0.25mole*6.02*10²³]/1mole = 1,505*10²³

4 0

4 years ago

Characteristics of crystal

Orlov [11]

Answer:

Crystalline solids, or crystals, have distinctive internal structures that in turn lead to distinctive flat surfaces, or faces. The faces intersect at angles that are characteristic of the substance. When exposed to x-rays, each structure also produces a distinctive pattern that can be used to identify the material.

Explanation:

5 0

3 years ago

PLEASE HELP!!!!!!

pogonyaev

Answer:

$m_{B}^{theoretical}=0.365gB$

$Y=87.1\%$

Explanation:

Hello there!

In this case, since the reaction (A->B) have an initial amount of pure 4-aminobenzoic acid, the first step to compute the theoretical yield is to solve the following stoichiometric setup:

$m_{B}^{theoretical}=0.303gA*\frac{1molA}{137.14gA}*\frac{1molB}{1molA}*\frac{165.19 gB}{1molB}\\\\ m_{B}^{theoretical}=0.365gB$

Whereas A stands for 4-aminobenzoic acid and B for the benzocaine. Moreover, we compute the percent yield by dividing the actual yield (0.318 g) by the theoretical one (0.365 g):

$Y=\frac{0.318g}{0.365g} *100\%\\\\Y=87.1\%$

Best regards!

4 0

3 years ago