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3 years ago

A 125-g sample of Fe2O3 contains how many moles?

Chemistry

1 answer:

dem82 [27]3 years ago

4 0

Answer:

To find the number of moles we must first calculate the molar mass( M) of Fe2O3

Molar mass = mass / number of moles

M(Fe2O3) = (55.8 ×2) + (16×3)

= 111.6 + 48

= 159.6 g/mol

number of moles = mass / molar mass

= 125g/159.6g/mol

= 0.783mol

Hope this helps

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3 years ago

6) (a) Calculate the absorbance of the solution if its concentration is 0.0278 M and its molar extinction coefficient is 35.9 L/

Anvisha [2.4K]

Answer:

6) (a) 0.499; (b) 31.7 %

7) 0.15

Explanation:

6) (a) Absorbance

Beer's Law is

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(b) Percent transmission

$A = \log {\left (\dfrac{1}{T}}\right)}\\\\\%T = 100T\\\\T = \dfrac{\%T}{100}\\\\\dfrac{1}{T} = \dfrac{100 }{\%T}\\\\A = \log \left(\dfrac{100 }{\%T} \right ) = 2 - \log \%T\\\\0.499 = 2 - \log \%T\\\\\log \%T = 2 - 0.499 = 1.501\\\\\%T = 10^{1.501} = \mathbf{31.7}$

7) Absorbance

$A = \log \left (\dfrac{I_{0}}{I} \right ) = \log \left (\dfrac{I_{0}}{0.70I_{0}} \right ) = \log \left (\dfrac{1}{0.70} \right ) = -\log(0.70) = \mathbf{0.15}}$

8 0

3 years ago

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Inessa05 [86]

Answer:

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Explanation:

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2 years ago

Potassium and fluorine are both halogens?

andreev551 [17]

Answer:

false, Potassium and fluorine are not halogens.

only fluorine here is halogen.

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is a non metal which comes under halogen family.

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2 years ago

Breathing equipment used by rescue workers needs to capture the CO2 the humans breath out and produce O2 for them to breath in,

const2013 [10]

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Explanation:

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The balanced chemical equation for reaction of potassium superoxide with carbon dioxide to produce oxygen and potassium carbonate will be:

$4KO_2+2CO_2\rightarrow 2K_2CO_3+3O_2$

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2 years ago