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3 years ago

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Suppose you were preparing 1.0 L of a bleaching solution in a volumetric flask, and it calls for 0.21 mol of NaOCl. If all you h

ad available was a jug of bleach that contained 0.82 M NaOCl, what volume of bleach would you need to add to the volumetric flask before you added enough water to reach the 1.0 L line?

2 answers:

Ilya [14]3 years ago

7 0

Answer:

V₁ = 0.26 L

Explanation:

The final solution requires 0.21 moles in V₂ = 1.0 L, which means a concentration of C₂ = 0.21 mol / 1.0 L = 0.21 M. The concentration of the initial solution is C₁ = 0.82 M. We can find the volume V₁ required using the dilution rule.

C₁ × V₁ = C₂ × V₂

0.82 M × V₁ = 0.21 M × 1.0 L

V₁ = 0.26 L

yulyashka [42]3 years ago

3 0

Answer:

0.256 L

Explanation:

We should use the following formula:

concentration (1) × volume (1) = concentration (2) × volume (2)

concentration (1) = 0.82 M NaOCl

volume (1) = ?

concentration (2) = 0.21 M NaOCl

volume (2) = 1 L

volume (1) = [concentration (2) × volume (2)] / concentration (1)

volume (1) = [0.21 / 1] / 0.82 = 0.256 L

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Answer:

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Explanation:

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assuming degree of dissociation $\alpha$ =1/10;

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$K_a = {c\alpha \times \alpha}$

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Explanation:

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--> METAMORPHIC ROCKS: These are the type of rocks which are formed by temperature and pressure changes inside the Earth.

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The actions that must have affected the igneous rock in order to form the sedimentary rock is that the igneous rocks are broken down into smaller pieces by erosion and weathering processes. Sediments which are formed accumulates at the earth surface. Over a long period of time, these sediments builds successive layers on top of one another. The sediments near the base hardens to form sedimentary rocks. This justifies the statement as a correct option (It must have been broken down into sediments).

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Explanation:

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Rina8888 [55]

Answer:

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