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2 years ago

3) Calculate the percent by mass of 3.55 g NaCl dissolved in 88 g water.

Chemistry

1 answer:

kotykmax [81]2 years ago

5 0

Answer:

The percent by mass of 3.55 g NaCl dissolved in 88 g water is 3.88%

Explanation:

When a solute dissolves in a solvent, the mass of the resulting solution is a sum of the mass of the solute and the solvent.

A percentage is a way of expressing a quantity as a fraction of 100. In this case, the percentage by mass of a solution is the number of grams of solute per 100 grams of solution and can be represented mathematically as:

$Percent by mass=\frac{mass of solute}{mass of solution} *100$

In this way it allows to precisely establish the concentration of solutions and express them in terms of percentages.

In this case:

mass of solute: 3.55 g
mass of solution: 3.55 g + 88 g= 91.55 g

Replacing:

$Percentbymass=\frac{3.55}{91.55}*100$

Percent by mass= 3.88%

<u><em>The percent by mass of 3.55 g NaCl dissolved in 88 g water is 3.88%</em></u>

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Setting up the radioactive rate equation:

$ln\frac{A_{t} }{A_{0} } =-kt$

Where $A_{t} = Activity after time t = 0.80microCi$

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$ln\frac{0.80uCi}{6.4uCi} =-(1.21*10^{-4}yr^{-1})t$

ln 0.125 = $-(1.21*10^{-4}yr^{-1})t$

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Therefore age of the painting based in the radiocarbon -14 dating studies is 17185 years

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2 years ago

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Anna [14]

Answer:

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1 year ago

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1 mole of $B_2H_6$ gives = 1 mole of $B_2O_3$

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Katyanochek1 [597]

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