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3 years ago

You start with 12.94 g sample of a mixture containing SiO2, NaCl, and NH4Cl. If after subliming

Chemistry

1 answer:

Tema [17]3 years ago

8 0

<h3>Answer:</h3>

83.23 %

<h3>Explanation:</h3>

<u>We are given;</u>

Mass of the sample mixture is 12.94 g
Mass of the remaining mixture after sublimation is 2.17 g

We are required to get the mass percent of NH₄Cl in the original sample

<h3>Step 1 : Calculate mass of NH₄Cl in the original sample;</h3>

Mass of NH₄Cl = Total mass of the mixture - remaining mass after sublimation

= 12.94 g - 2.17 g

= 10.77 g

<h3>Step 2: Percent by mass of NH₄Cl in the original sample</h3>

% of NH₄Cl by mass =(Mass of NH₄Cl÷Total mass of original sample)×100

= (10.77 g ÷ 12.94 g) × 100

= 83.23 %

Therefore, the percent by mass of NH₄Cl in the original sample is 83.23%

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Aspirin (C9H8O4) is synthesized by reacting salicylic acid (C7H6O3) with acetic anhydride (C4H6O3). The balanced equation isC7H6

prisoha [69]

<u>Answer:</u>

<u>For a:</u> The mass of acetic anhydride needed is 73.91 grams.

<u>For b:</u> The theoretical yield of aspirin is 130.43 grams.

<u>Explanation:</u>

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

<u>For a:</u>

Given mass of salicylic acid = $1.00\times 10^2g=100g$

Molar mass of salicylic acid = 138.121 g/mol

Putting values in equation 1, we get:

$\text{Moles of salicylic acid}=\frac{100g}{138.121g/mol}=0.724mol$

For the given chemical reaction:

$C_7H_6O_3+C_4H_6O_3\rightarrow C_9H_8O_4+CH_3COOH$

By stoichiometry of the reaction:

1 mole of salicylic acid reacts with 1 mole of acetic anhydride.

So, 0.724 moles of salicylic acid will react with = $\frac{1}{1}\times 0.724=0.724mol$ of acetic anhydride.

Now, to calculate the mass of acetic anhydride, we use equation 1:

Moles of acetic anhydride = 0.724 moles

Molar mass of acetic anhydride = 102.09 g/mol

Putting values in equation 1, we get:

$0.724mol=\frac{\text{Mass of acetic anhydride}}{102.09g/mol}\\\\\text{Mass of acetic anhydride}=73.91g$

Hence, the mass of acetic anhydride needed is 73.91 grams.

<u>For b:</u>

By stoichiometry of the reaction:

1 mole of salicylic acid is producing 1 mole of aspirin.

So, 0.724 moles of salicylic acid will produce = $\frac{1}{1}\times 0.724=0.724mol$ of aspirin.

Now, to calculate the mass of aspirin, we use equation 1:

Moles of aspirin = 0.724 moles

Molar mass of aspirin = 180.158 g/mol

Putting values in equation 1, we get:

$0.724mol=\frac{\text{Mass of aspirin}}{180.158g/mol}\\\\\text{Mass of aspirin}=130.43g$

Hence, the theoretical yield of aspirin is 130.43 grams.

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In order to improve the condition of your muscular system, you could participate in aerobic activity at least __________. A. 3 m

zlopas [31]

I think it would be C

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Sodium thiosulfate, Na 2S 2O 3, is used as a "fixer" in black and white photography. Identify the reducing agent in the reaction

Tatiana [17]

Answer: Reducing agent in the given reaction is $S_{2}O^{2-}_{3}$ .

Explanation:

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Carbon exists in nature as three isotopes. Given the atomic masses and relative abundance of the isotopes, what is the average a

Ivan

The most abundant carbon isotope is carbon-12.

The relative atomic mass of carbon is 12.011, which is extremely close to 12.0. This means that the masses C-13, and C-14 are practically negligible when contributing to the relative atomic mass of carbon.

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Arturiano [62]

Answer:

Explanation:

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