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2 years ago

Determine the percent composition by mass of a 100g salt solution which contains 20g salt

Chemistry

2 answers:

prisoha [69]2 years ago

8 0

Answer:

Mass of solution=100g

mass of salt=20g

so; mass of solute=80g

percentage composition =(mass of salt/total

mass) ×100

= \frac{20}{100} \times 100 \\ = 20\%

glad to help you

hope it helps

lara [203]2 years ago

8 0

The percent composition by mass of a 100g salt solution which contains 20g salt is $\bold{16.6\%}$

Solution:

Percent composition is calculated as, weight of the solute divided by amount of solute added to 100 g is solution multiplied by 100.

$\Rightarrow \frac{\text {weight of solute}(g)}{\text {weight of solute}(g)+\text {weight of solution(g)}} \times 100$

Given, 100 g of salt solution with 20 g of salt

Weight of the solute and solvent is $20 + 100 g = 120 g$

$percent composition=\frac{20}{120} \times 100=\frac{200}{12}=16.6$

$\therefore \text { percent composition } =16.6 \%$

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Half-life time is the time needed for the reactants to be in its half concentration.

The sample stats with 56.0 g and reaches its half concentration (28.0 g) after 1,600 years.

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For, first order reactions:

k = ln(2)/(t1/2) = 0.693/(t1/2).

Where, k is the rate constant of the reaction.

t1/2 is the half-life of the reaction.

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Also, we have the integral law of first order reaction:

kt = ln([A₀]/[A]),

where, k is the rate constant of the reaction (k = 4.33 x 10⁻⁴ year⁻¹).

t is the time of the reaction (t = ??? year).

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The correct answer is b movement between different compartments(Such as between water and air).

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2 years ago

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As we are given,

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