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Arturiano [62]
3 years ago
5

In the soap testing experiment, what is the purpose of adding some MgCl2 to the soap solution at the end?

Chemistry
1 answer:
lakkis [162]3 years ago
4 0

Explanation:

The water is hard due to the presence of ions of Mg²⁺. Now in hard water soaps are ineffective . Since in hard water Mg²⁺ ion forms precipitate , which concludes less number of soap molecules are present in the solution and less amount of  froth  which disables the cleansing property of the soap .

Now the experiment , the very last step is the hard water test where some amount of MgCl₂ is added ,

Now this magnesium salt act as a source of Mg²⁺ ion and now the soap action can be determined , whether it is able to form froth or not .

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sasho [114]

Answer:

8.937g/cm³

Explanation:

To answer this question we need to know that, in 1 unit FCC cell you have:

Edge length = √8 * R

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<em>And there are 4 atoms per unit cell</em>

<em />

<em>Mass of 4 atoms in g:</em>

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Volume = 8√8 * (1.278x10⁻⁸cm)³

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6 0
4 years ago
When burned, coal releases _____. oxygen carbon dioxide methane sulfur nitrogen oxide?
Rus_ich [418]
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Explanation:

4 0
3 years ago
Which of these solutions are basic at 25 °C? Solution A: [OH−]=3.13×10−7 M Solution C: [H3O+]=0.000747 M Solution B: [H3O+
solong [7]

Answer:

Are basic:

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Explanation:

A solution is basic when pH = - log [H₃O⁺] is higher than 7.

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[H₃O⁺] = 1x10⁻¹⁴ / [OH⁻]

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[H₃O⁺] = 3.19x10⁻⁸M

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This solution is not basic

c. [H₃O⁺] = 9.55x10⁻⁹M

pH = 8.02

This solution is also basic.

8 0
3 years ago
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