Chemistry, 11.07.2019 21:30 aprilstalder

Asample was prepared by mixing 18. ml of 3.00 x 10^-3 m crystal violet (cv) with 2.00 ml of 0.250 m naoh. calculate the resulting concerntattions of cv and oh-

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The study of chemicals is called chemistry. The concentration of the solution depends on the amount of solute present in it.

The correct answer is 0.025M.

What is molarity?Molar concentration is a measure of the concentration of a chemical species, in particular of a solute in a solution, in terms of the amount of substance per unit volume of solution.The moles of crystal violet and NaOH is as follows:-

The molarity formula is = $M=\frac{MOLE}{V}$

The volume of crystal violet solution is 18 mL which is 0.018 L

Moles of crystal violet = $3*10^{-3}*0.018=5.4*10^{-5}$

Hence, Moles of crystal violet = $5.4 * 10^{-5}$

The total volume of the solution

The total volume of the solution after mixing NaOH and crystal violet is

0.018 L + 0.00200 = 0.020 L

Molarity formula to find final concentrations

Molarity of crystal violet = $\frac{5.4*10^{-5}}{0.020} =2.7*10^{-3}$ .

Final concentration of CV = 0.0027 M

Molarity of NaOH= $\frac{5*10^{-4}}{0.020} =0.025*10^{-3}$

Hence, The mole ratio of NaOH and OH⁻ is 1:1. Therefore the concentration of OH⁻ is the same as that of NaOH.

The required Concentration of OH⁻ is 0.025 M.

For more information about the molarity, refer to the link:-

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Answer from: Zaxx2974

Answer : The resulting concentrations of CV and NaOH are 0.0027 M and 0.025 M respectively.

Explanation :

Step 1 : Find moles of crystal violet and NaOH.

The molarity formula is

$Molarity = \frac{mol}{L}$

Molarity of crystal violet = $3.00 \times 10^{-3} = \frac{mol (CrystalViolet)}{L}$

The volume of crystal violet solution is 18 mL which is 0.018 L.

Moles of crystal violet = $3.00 \times 10^{-3} \times 0.018 = 5.4 \times 10^{-5}$

Moles of crystal violet = 5.4 x 10⁻⁵

Moles of NaOH = $Molarity \times L = 0.250 \times 0.00200 = 5.00 \times 10^{-4}$

Moles of NaOH = 5.00 x 10⁻⁴

Step 2 : Find total volume of the solution

The total volume of the solution after mixing NaOH and crystal violet is

0.018 L + 0.00200 = 0.020 L

Step 3 : Use molarity formula to find final concentrations

Molarity of crystal violet = $\frac{mol(CrystalViolet)}{Total Volume(L) } = \frac{5.4 \times 10^{-5}}{0.020} = 2.7 \times 10^{-3}$

Final concentration of CV = 0.0027 M

Molarity of NaOH= $\frac{mol(NaOH)}{Total Volume(L) } = \frac{5.00 \times 10^{-4}}{0.020} = 0.025 \times 10^{-3}$

NaOH is a strong base and dissociates completely as follows.

$NaOH (aq) \rightarrow Na^{+} (aq) + OH^{-} (aq)$

The mole ratio of NaOH and OH⁻ is 1:1 . Therefore the concentration of OH⁻ is same as that of NaOH.

Concentration of OH⁻ = 0.025 M

Answer from: Quest

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explanation:

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