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2 years ago

How many atoms are there in 90.2 g of selenium?

1 answer:

3 0

Answer:First calculate the moles of selenium by multiplying the mass x molar mass 90.2 × 78.96 = 7122.2 moles. Number of moles multiplied by ...

Explanation:

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Aspirin can be prepared from salicylic acid ( C 7 H 6 O 3 CX7HX6OX3), which has a molar mass of 138.12 g/mol, and acetic anhydri

pychu [463]

Answer: The theoretical yield of aspirin is 4.14 g

Explanation:

To calculate the moles :

$\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}$ $\text{Moles of salicylic acid}=\frac{3.20g}{138.12g/mol}=0.023moles$

mass of acetic anhydride = $density\times volume =1.082g/ml\times 3.71ml=4.01g$

$\text{Moles of acetic anhydride}=\frac{4.01g}{102.04g/mol}=0.039moles$

$C_9H_6O_3+C_4H_6O_3\rightarrow C_9H_8O_4+C_2H_3O_2$

According to stoichiometry :

1 mole of salycylic acid require 1 mole of acetic anhydride

Thus 0.023 moles of salycylic acid require= $\frac{1}{1}\times 0.023=0.023moles$ of acetic anhydride

Thus salycylic acid is the limiting reagent as it limits the formation of product and acetic anhydride is the excess reagent.

As 1 mole of salycylic give = 1 mole of aspirin

Thus 0.023 moles of salycylic acid give = $\frac{1}{1}\times 0.023=0.023moles$ of aspirin

Mass of aspirin = $moles\times {\text {Molar mass}}=0.023moles\times 180.15g/mol=4.14g$

Thus theoretical yield of aspirin is 4.14 g

4 0

2 years ago

Annabelle was explaining the carbon cycle to her friend. She said that all the carbon

vagabundo [1.1K]

Answer: O2+6H12O6=CO2+ENERGY(ATP)

I DON'T THINK SHE IS CORRECT

Explanation:

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2 years ago

Determine the number of equivalents if a 3.89N solution contains 0.76 L of solution

ValentinkaMS [17]

Answer:

Explanation:

oriented C-2, and (3) the minimizing of the number of ... (2) L. A. Mitscher, J. K. Paul, and L. Goldman,Experientia, 19, 195. (1963). ... SOzCeHiBr)3 in 147 ml. of anhydrous methanol containing 0.37 ... bicarbonate and saturated sodium chloride solution, and dried ... determined in 2% chloroform solution; infrared spectra on.

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2 years ago

What two elements in the sun mostly made of

ivanzaharov [21]

The sun is made up of two main elements, hydrogen and helium.

Hydrogen makes up about 92% of all of the atoms in the sun while helium makes up about 7.8%.
Oxygen, carbon, neon and nitrogen make up most of the remaining 0.2%.

8 0

2 years ago

Please help me !!!!?:(

atroni [7]

True, a lunar eclipse occurs when the Moon is between the Sun and Earth

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2 years ago