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2 years ago

What is the number of copper atom in one naira coin which weight is 7.3g a sum of the material is 86%

Chemistry

1 answer:

Step2247 [10]2 years ago

4 0

Answer:

5.9x10²² atoms of Cu are in one naira coin

Explanation:

To solve this question we need to find the mass of Copper. Then, using its molar mass (Cu = 63.546g/mol) we must find the moles of Cu and its atoms using Avogadro's number:

Mass Cu:

7.3g * 86% = 6.278g is the mass of Cu.

Moles Cu:

6.278g * (1mol / 63.546g) = 0.099moles Cu

Atoms Cu:

0.099moles Cu * (6.022x10²³atoms / 1mol) =

<h3>5.9x10²² atoms of Cu are in one naira coin</h3>

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Answer:

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Explanation:

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Now another formula for thermal efficiency Is

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3 years ago

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wlad13 [49]

Answer:

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V = IR

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V = voltage (Volts)

I = current (amperes)

R = resistance (ohms)

According to the information provided in the question, resistance (R) = 13 Ohm, current (I) = 1.24 Amperes, V = ?

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