CHEMISTRY HIGH SCHOOL

in a sample of silcon 92.21% of the atoms have a mass of 27.98 amu, 4.70% have a mass of 28.98 amu and 3.09% have a mass of 29.97 amu. what is ther average atomic mass of the sample? socratic.org socratic.org

Answers

Answer 1

Answer:

Answer: 28.1 amu

Explanation:

Mass of isotope 1 = 27.98 amu

% abundance of isotope 1 = 92.21% = $(92.21)/(100)=0.9221$

Mass of isotope 2 = 28.98 amu

% abundance of isotope 2 = 4.70% = $(4.70)/(100)=0.047$

Mass of isotope 3 = 29.97 amu

% abundance of isotope 2 = 3.09% = $(3.09)/(100)=0.0309$

Formula used for average atomic mass of an element :

$\text{ Average atomic mass of an element}=\sum(\text{atomic mass of an isotopes}* {{\text { fractional abundance}})$

$A=\sum[(27.98 )* 0.922+(28.98)* 0.047+(29.97)* 0.0309]$

$A=28.1amu$

Therefore, the average atomic mass of silicon is 28.1 amu

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Answers

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Answers

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Answer:

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Answers

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Final answer:

The total amount of energy in the cooler remains the same. The warm soda transfers its heat energy to the ice, causing the soda to cool and the ice to melt. The cooler, soda, and water from the melted ice eventually reach a thermal equilibrium where they have the same temperature.

Explanation:

In the scenario where a student puts a warm can of soda in a cooler filled with ice, the amount of thermal energy in the cooler's system changes due to the process of heat transfer. This process follows the second law of thermodynamics which stipulates that heat tends to flow from hotter objects to colder objects until they reach equilibrium.

In this case, the warmer soda will transfer its heat to the colder ice. During this process, the ice will absorb the heat without a rise in temperature until all of it has melted. This is because this absorbed energy is used to break the bonds holding the ice molecules together in a solid state, causing a phase change to liquid water.

Simultaneously, the soda can's temperature drops as it loses heat to the ice. Eventually, everything in the cooler—the soda, the melted ice water, and the air within—will reach the same temperature, marking the achievement of thermal equilibrium. Therefore, the total amount of energy in the cooler remains the same, it's just transferred (not lost or gained). The energy initially within the can of soda is transferred to the ice, and the overall rise in the cooler’s temperature represent this energy transfer.

Learn more about Heat Transfer here:

brainly.com/question/13433948

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Answers

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Answer:

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Answers

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