The answer is 64.907 amu.
The atomic mass of an element is the average of the atomic masses of its isotopes. The relative abundance of isotopes must be taken into consideration, therefore:
atomic mass of copper = atomic mass of isotope 1 * abundance 1 + atomic mass of isotope 2 * abundance 2
We know:
atomic mass of copper = 63.546 amu
The atomic mass of isotope 1 is: 62.939 amu
The abundance of isotope 1 is: 69.17% = 0.6917
The atomic mass of isotope 1 is: x
The abundance of isotope 2: 100% - 69.17% = 30.83% = 0.3083
Thus:
63.546 amu = 62.939 amu * 0.6917 + x * 0.3083
63.546 <span>amu = 43.535 amu + 0.3083x
</span>⇒ 63.546 amu - 43.535 amu = 0.3083x
⇒ 20.011 amu = 0.3083x
⇒ x = 20.011 amu ÷ 0.3083 = 64.907 amu
N₂, H₂, NH₃ are present in the reaction mixture when equilibrium has been obtained.
Balanced chemical reaction: 3H₂ + N₂ ⇄ 2NH₃
Hydrogen (H₂ ) and nitrogen (N₂) are reactants.
Ammonia (NH₃) is product of the reaction.
Reaction goes in both direction, both reactants and product are present.
The amount of substance of reactants and products of reaction do not change when chemical reaction is in chemical equilibrium.
In a chemical reaction, chemical equilibrium is the state in which both reactants and products are present in concentrations which not change with time.
Speed of direct and irreversible chemical reaction are equal.
More about equilibrium: brainly.com/question/25651917
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