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3 years ago

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Urgent‼️‼️‼️‼️‼️‼️ Find the average atomic mass of element Uus. 284Uus 283.4 amu 34.60 % 284.7 amu 21.20 % Uus 287.8 amu 44.20 %

285Uus 288

1 answer:

Citrus2011 [14]3 years ago

4 0

Answer:

285.6

Explanation:

(283.4×0.3460)+(284.7×0.2120)+(287.8×0.4420)

=285.6204

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We can answer this question applying the Le Chatelier's Principle. It says that changes on pressure, volume or temperature of an equilibrium reaction will change the reaction direction until it returns to the equilibrium condition again.

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So, when 1 mole of hydrogen peroxide will react, the enthalpy of the reaction will be $\frac{-196}{2}\times 1=-98kJ$

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$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

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To calculate the heat of the reaction, we use the equation:

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Putting values in above equation, we get:

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