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2 years ago

A sample of the mineral hematite Iron (III) oxide has a mass of 12.4g. How many moles of the mineral are present?

1 answer:

8 0

Thus problem is providing us with the mass of iron (III) oxide as 12.4 g so the moles are required and found to be 0.0776 mol after the calculations:

<h3>Mole-mass relationships:</h3>

In chemistry, we use mole-mass relationships in order to calculate grams from moles and vice versa. In this case, since we are given the mass of iron (III) oxide as 12.4 g one can calculate the moles by firstly quantifying its molar mass:

$Fe_2O_3\rightarrow 2*55.85 g/mol+3*16.00 g/mol=159.7g/mol$

Then, we prepare a conversion factor in order to cancel out the grams and thus, get moles:

$12.4gFe_2O_3*\frac{1molFe_2O_3}{159.7gFe_2O_3} \\\\=0.0776molFe_2O_3$

Learn more about mole-mass relationships: brainly.com/question/18311376

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The answer to your question is: letter D

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2 years ago

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_____ is a measure of the average kinetic energy of a gas. Density Enthalpy Pressure Temperature

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Answer:

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Explanation:

Temperature is a measure of the average kinetic energy of the particles in a sample of a gas.
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3 years ago

A total of 663 cal 663 cal of heat is added to 5.00 g 5.00 g of ice at − 20.0 °C . −20.0 °C. What is the final temperature of th

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Answer:

Final Temperature = 305.9 K or 32.9°C

Explanation:

Information given;

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Final Temperature?

Specific Heat capacity of Water (c) =?

One might probably rush to use H = m * c * (T2-T1) to calculate the fianl temperature. That would have been wrong because Ice would melt when heat is being applied to it. And using that formular directly would lead to not considering the amount of heat required to melt it.

First let us check the amount of heat required to raise the temperature of the ice to 0°C

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if you have any questions, leave them in the comments and i will try to answer them, if this helped, pls give brainliest.

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