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3 years ago

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A chemist prepares a solution of sodium carbonate by measuring out of sodium carbonate into a volumetric flask and filling the f

lask to the mark with water. Calculate the concentration in of the chemist's sodium carbonate solution. Be sure your answer has the correct number of significant digits.

1 answer:

Vadim26 [7]3 years ago

8 0

Answer:

The correct answer will be " $9.45\times 10^{-5} \ mol/L$ ".

Explanation:

We have:

Moles of solute (Na₂Co₃) = $18.9 \mu \ mol$

= $18.9\times 10^{-6}$

$1 \mu \ mol$ = $10^{-6} \ mol$

Now,

The volume of the solution will be:

⇒ $0.200 \ L$

∴ ${1 \ mL=0.001 \ L}$

The formula to find the concentration will be:

⇒ $Concentration = \frac{moles \ of \ solute \ (mol)}{Volume \ of \ solution \ (L)}$

On substituting the given values, we get

⇒ $=\frac{18.9\times 10^{-6}}{0.200}$

⇒ $=9.45\times 10^{-5} \ mol/L$

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Triss [41]

Explanation:

For the first part,

Reaction equation:

N₂ + 3H₂ → 2NH₃

Given:

Number of moles of NH₃ = 6 moles

Unknown:

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Solution:

N₂ + 3H₂ → 2NH₃;

From the reaction above, we solve from the known specie to the unknown. Ensure that the equation is balanced;

2 moles of NH₃ is produced from 1 mole of N₂

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ii.

Given parameters:

Number of moles of sulfur = 2.4moles

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Sholpan [36]

Answer:

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where;

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$k = \frac{0.693}{t__{1/2}}$

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frosja888 [35]

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