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3 years ago

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Chemistry

1 answer:

vovangra [49]3 years ago

3 0

Answer:

Keep the temperature at 20°C. Stir the solution

Explanation:

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The decomposition of 3.32 g CaCO3 yields 1.24 g CaO. What is the percent yield of this reaction? (CaCO3 --> CaO + CO2)

alex41 [277]

Answer:

66.57%

Explanation:

The decomposition reaction of calcium carbonate is shown below as:

$CaCO_3\rightarrow CaO+CO_2$

Calculation of moles of $CaCO_3$ :

Amount = 3.32 g

Molar mass of $CaCO_3$ = 100 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus, moles are:

$moles= \frac{3.32\ g}{100\ g/mol}$

$moles= 0.0332\ mol$

According to reaction,

0.0332 moles of $CaCO_3$ decomposes to yield 0.0332 moles of $CaO$

Theoretical yield = 0.0332 moles

Calculation of moles of $CaO$ formed as:

Amount = 1.24 g

Molar mass of $CaO$ = 56 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus, moles are:

$moles= \frac{1.24\ g}{56\ g/mol}$

$moles= 0.0221\ mol$

Experimental yield = 0.0221 moles

$Yield\%=\frac {Experimental yield}{Theoretical yield}\times 100$

Thus,

$Yield\%=\frac {0.0221}{0.0332}\times 100$

Percent yield = 66.57%

5 0

4 years ago

Manganese (Mn) is a silver-colored metal. It

vladimir1956 [14]

Answer:

Explanation:

Manganese (Mn) is a silver-colored metal. It reacts with oxygen to form manganese oxide (MnO2), which has two oxygen atoms for every manganese atom. Which statement describes the properties of manganese oxide? It will be a gas because there are more oxygen atoms.

8 0

3 years ago

How many moles are in 2.12g Cr2O3

ohaa [14]

Answer:

0.01395mol Cr2O3

Explanation:

the molar mass of Cr2O3 is 151.9904 g/mol

2.12g Cr2O3 x 1 mol/151.9904g = 0.01395mol Cr2O3

4 0

3 years ago

Give two examples in which the host is harmed.

dexar [7]

Answer:

lice, mosquito

Explanation:

both are examples of parasitism

edit: wait nvm i thought this was bio

7 0

4 years ago

When heat is applied to 80 grams of CaCO3, it yields 39 grams of B. Determine the percentage of the yield.

EleoNora [17]

The question is incomplete, the complete question is:

When heat is applied to 80 grams of CaCO3, it yields 39 grams of CaO Determine the percentage of the yield.

CaCO3→CaO + CO2

Answer: The % yield of the product is 87.05 %

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass.

The equation used is:

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

We are given:

Given mass of $CaCO_3$ = 80 g

Molar mass of $CaCO_3$ = 100 g/mol

Putting values in equation 1, we get:

$\text{Moles of }CaCO_3=\frac{80g}{100g/mol}=0.8mol$

For the given chemical reaction:

$CaCO_3\rightarrow CaO+CO_2$

By stoichiometry of the reaction:

If 1 mole of $CaCO_3$ produces 1 mole of CaO

So, 0.8 moles of $CaCO_3$ will produce = $\frac{1}{1}\times 0.8=0.8mol$ of CaO

We know, molar mass of $CaO$ = 56 g/mol

Putting values in above equation, we get:

$\text{Mass of CaO}=(0.8mol\times 56g/mol)=44.8g$

The percent yield of a reaction is calculated by using an equation:

$\% \text{yield}=\frac{\text{Actual value}}{\text{Theoretical value}}\times 100$ ......(2)

Given values:

Actual value of the product = 39 g

Theoretical value of the product = 44.8 g

Plugging values in equation 2:

$\% \text{yield}=\frac{39 g}{44.8g}\times 100\\\\\% \text{yield}=87.05\%$

Hence, the % yield of the product is 87.05 %

6 0

3 years ago