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3 years ago

7

Calculate molality of a 2m aq solution of sodium chloride with density 1.35g/mol

1 answer:

swat323 years ago

5 0

There are a number of ways to express concentration of a solution. This includes molarity and molality. Molarity is expressed as the number of moles of solute per volume of the solution while molality is expressed as the number of moles solute per mass of solution. Calculation is as follows:

(2 mol NaCl / L solution) ( 1 cm^3 / 1.35 g) ( 1000 L / 1 cm^3) (1000 g /kg) = 1.5 x 10^6 mol / kg solution

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3 years ago

If a gaseous mixture is made by combining 2.74 g Ar 2.74 g Ar and 4.90 g Kr 4.90 g Kr in an evacuated 2.50 L container at 25.0 ∘

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3 years ago

Carbon-14 has a half-life of 5720 years and this is a first order reaction. If a piece of wood has converted 75% of the carbon-1

liraira [26]

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$k=\frac{0.693}{5720\text{years}}$

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8 0

3 years ago

Read 2 more answers

Calculating the Molecular Weight and Subunit Organization of a Protein From Its Metal Content The element molybdenum (atomic wei

Deffense [45]

Answer:

Dimer of two peptide chains with 1 mole of molybdenum metal each.

Explanation:

Percentage of molybdenum in protein = 0.08%

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Mass of molybdenum = x

$0.08\%=\frac{x}{240,000 g}\times 100=192 g$

Moles of molybdenum = $\frac{192 g}{95.95 g/mol}=2.00 mol$

Each peptide chain of nitrate reductase contain 1 mole of molybdenum.

This means that nitrate reductase is composed of to two peptide chains. And in each peptide there is a single mole of molybdenum metal.

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3 years ago