Nitrous acid<span> dissociates as follows:
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HNO₂(s) ⇄ H⁺(aq) + NO₂⁻(aq)
According to the equation, an acid constant has the following form:
Ka = [H⁺] × [NO₂⁻ ] / [HNO₂]
From pH, we can calculate the concentration of H⁺ and NO₂⁻:
[H⁺] = 10^-pH = 10^-2.63 = 0.00234 M = [NO₂⁻]
Now, the acid constant can be calculated:
Ka = 0.00234 x 0.00234 / 0.015 = 3.66 x 10⁻⁴
And finally,
pKa = -log Ka = 3.44
Solution : An oxidation reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between tow species an oxidaion reductin reaction is any chemical reaction in which the oxidation number of a molecule atom or ion changes by gaining or losing an electron
In order to solve this, we need to make use of Hess' Law.
We are already given the equations and their corresponding deltaH. Using Hess' Law, we can generate this equation:
104 kJ = x - (-1182 kJ) - (-1144 kJ)
Among the choices, the answer is
<span>B.104 = x - [(-1182) + (-1144)]
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The answer is: a relatively large electron cloud.
Atom is composed of the nucleus and the electron cloud.
Protons (positive particles) and neutrons (neutral particles) are in the nucleus of an atom and electrons (negative particles) are in the electron cloud.
Nucleus is in the centar of the atom atom and electron cloud is surrounding it.
Atoms have their mass concentrated in a very small nucleus.