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3 years ago

1. Din 800 grame soluţie de concentraţie 20% se evaporă 200 grame

Chemistry

1 answer:

mrs_skeptik [129]3 years ago

5 0

Percentage concentration after evaporated : 26.7%

<h3>Further explanation</h3>

From 800 grams of 20% concentration solution evaporate 200 grams

the water. What percentage concentration will the new solution obtained have?

From 800 g solution, mass of solute :

$\tt \%concentration\times mass~of~solution\\\\20\%\times 800=160~g$

mass of water :

$\tt 800-160=640$

After water evaporated :

$\tt 640-200=440~g$

mass solution after evaporated :

$\tt 440+160=600~g$

%concentration :

$\tt \dfrac{160}{600}\times 100\%=26.7\%$

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Answer:

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3 years ago

What is the mass of 3.0 x x times 10^23 atoms of neon?

Sladkaya [172]

Answer:

10.09 grams

Explanation:

First you need to know the number of moles you are dealing with.

If you know that each mole has 6.022x10²³ of something (in this case of atoms), you can divide 3x10²³ atoms of neons by 6.022x10²³ to obtain the number of moles.

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3 years ago

Substance A has the following properties.

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It will take 1.11 min to heat the sample to its melting point.

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C(liquid) = 2.5 J/g °C

C(gas) = 0.5 J/g °C

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Initial temperature = - 40°C

Final temperature = 100°C

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Here, q = heat energy

m = mass

C = specific heat

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Put these value in Specific heat capacity formula

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The Rate of heating = 450 J/min

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so, 500J = 1.11min

1.11 minutes does it take to heat the sample to its melting point.

The specific heat capacity is defined as the amount of heat absorbed in line with unit mass of the material whilst its temperature increases 1 °C.

Learn more about specific heat capacity here:- brainly.com/question/26866234

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1 year ago

explain how to determine the number of atoms, cations, and anions in ionic compounds. use an example to explain.

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Answer:

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Example:

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2 years ago

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zepelin [54]

Answer:

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On putting the values we get:

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= 0.0043447 mol * 28 g/mol

= 0.12 g

3 0

3 years ago