Answer:
6.25% of the original amount
Explanation:
half-life means that half is gone for every certain period of time. Because the half life is 1 month, only half of the 'radionulide' is left every month.
after 1 month= 50%
after 2 months= 25%
after 3 months= 12.5%
after 4 months= 6.25%
This answer to this question is a rule that is applied to any reaction taken at dynamic equilibrium, with respect to 500 K. In other words, you can say that this reaction is of no use to us -
In a chemical equilibrium, it is known that the forward and reverse reactions occur at equal rates. At this point the concentrations of products and reactants remain constant, or in other words do not change
<u><em>Solution = Option C</em></u>
Answer:
0.017 moles of ammonia remains after the reaction is stopped.
Explanation:
The reaction is:
4NH₃ + 5O₂ → 4NO + 6H₂O
The first step is to convert the mass to moles, of each reactant:
2 g . 1mol/ 17g = 0.117 moles of NH₃
4 g . 1mol /32g = 0.125 moles of O₂
Ammonia, states the question, is the excess reactant so we can confirm it,
5 moles of oxygen need 4 moles of ammonia to react (by stoichiometry)
Then, 0.125 moles of oxygen may react to (0.125 . 4) / 5 = 0.1 moles
As we have 0.117 moles of ammonia and we need 0.1 moles.
(0.117 - 0.1) = 0.017 moles remains after the reaction is completed.
If we convert the moles to mass we have:
0.017 mol . 17 g /1mol = 0.289 g