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timama [110]
2 years ago
7

Copper, a metal known since ancient times, exists in two stable isotopic forms, 6329Cu (69.09%) and 6529Cu (30.91%). Their atomi

c masses are 62.93 amu and 64.9278 amu respectively. Calculate the average atomic mass of copper.
Chemistry
1 answer:
Svetradugi [14.3K]2 years ago
7 0

Answer:

Wt. Avg. Atomic Weight => 63.35457 amu

Explanation:

Given              Isotopic             %Abundance     fractional          Wt Avg

                  At. Mass (amu)                                  abundance      contribution                    

Cu-63              62.93                      69.09              0.6909            43.4783

Cu-65              64.9278                  20.0668        0.200668        20.0668

Wt Average of all isotopes = ∑Wt Avg Contributions

=  43.4783 amu + 20.0668 amu = 63.35457 amu

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Answer: Fe:Cl2 = 2:3

Explanation:

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3 years ago
What factors affect the dynamic state of equilibrium in a chemical reaction and how?
yanalaym [24]

Answer:

Only changes in temperature will influence the equilibrium constant K_c. The system will shift in response to certain external shocks. At the new equilibrium Q will still be equal to K_c, but the final concentrations will be different.

The question is asking for sources of the shocks that will influence the value of Q. For most reversible reactions:

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For some reversible reactions that involve gases:

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Catalysts do not influence the value of Q. See explanation.

Explanation:

\displaystyle K_c = {e}^{\Delta G/(R\cdot T)}.

Similar to the rate constant, the equilibrium constant K_c depends only on:

  • \Delta G the standard Gibbs energy change of the reaction, and
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The reversible reaction is in a dynamic equilibrium when the rate of the forward reaction is equal to the rate of the backward reaction. Reactants are constantly converted to products; products are constantly converted back to reactants. However, at equilibrium Q = K_c the two processes balance each other. The concentration of each species will stay the same.

Factors that alter the rate of one reaction more than the other will disrupt the equilibrium. These factors shall change the rate of successful collisions and hence the reaction rate.

  • Changes in concentration influence the number of particles per unit space.
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For reactions that involve gases,

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However, there are cases where the number of gases particles on the reactant side and the product side are equal. Rates of the forward and backward reaction will change by the same extent. In such cases, there will not be a change in the final concentrations. Similarly, catalysts change the two rates by the same extent and will not change the final concentrations. Adding noble gases will also change the pressure. However, concentrations stay the same and the equilibrium position will not change.

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2 years ago
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marshall27 [118]

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Explanation:

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Final molarity of the solution =75.0 \mathrm{mM}

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From Law of Dilution, M_{f} V_{f}=M_{i} V_{i}

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Explanation:

Hello! Let's solve this!

We will analyze each of the options:

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