For my opinion 2nd last statement is better
Answer:
pH = 2.462.
Explanation:
Hello there!
In this case, according to the reaction between nitrous acid and potassium hydroxide:
It is possible to compute the moles of each reactant given their concentrations and volumes:
Thus, the resulting moles of nitrous acid after the reaction are:
So the resulting concentration considering the final volume (20.00mL+13.27mL) is:
![[HNO_2]=\frac{6.73x10^{-4}mol}{0.01327L+0.02000L} =0.02023M](https://tex.z-dn.net/?f=%5BHNO_2%5D%3D%5Cfrac%7B6.73x10%5E%7B-4%7Dmol%7D%7B0.01327L%2B0.02000L%7D%20%3D0.02023M)
In such a way, we can write the ionization of this weak acid to obtain:
So we can set up its equilibrium expression to obtain x as the concentration of H3O+:
![Ka=\frac{[NO_2^-][H_3O^+]}{[HNO_2]}\\\\7.1x10^{-4}=\frac{x^2}{0.02023M-x}](https://tex.z-dn.net/?f=Ka%3D%5Cfrac%7B%5BNO_2%5E-%5D%5BH_3O%5E%2B%5D%7D%7B%5BHNO_2%5D%7D%5C%5C%5C%5C7.1x10%5E%7B-4%7D%3D%5Cfrac%7Bx%5E2%7D%7B0.02023M-x%7D)
Next, by solving for the two roots of x, we get:
Whereas the correct value is 0.003451 M. Finally, we compute the resulting pH:
Best regards!
The periodic table of the elements are describe the electronic configuration of the elements on which the properties of the elements depends. Among the given groups only metal, non-metal and semi-metal group are the part of periodic table. The metallic property depends upon the binding energy of the electrons with the nucleus. Thus the elements which have the valence electrons more near to the nucleus that is s-block elements are more metallic in nature. On the other hand the elements which have the valence electrons far from the nucleus are more non-metallic in nature like p-block elements. However the binding energy or the attraction of the outermost electrons to the nucleus depends not only its valence electrons position but also some other factors like shielding effect, effective nuclear charge etc.
The elements which are in between the metals and non-metals can be classified as semi-metals.
Although the conductivity of a material is an inherent property of the metals but sometime the nonmetals or semi-metals are also behave like a conductor due to presence of the other elements, thus it cannot be a p[property of the periodic table. Similarly acidity, flammable gases are not part of the periodic table.
Answer:
1
Explanation:
Consider the following reaction:
Phosphorus burn in the presence of air and produced diphosphorus pentoxide.
Chemical equation:
P₄ + O₂ → P₂O₅
Balanced chemical equation:
P₄ + 5O₂ → 2P₂O₅
Equation is balanced because there are four phosphorus atoms ans ten oxygen atoms in both side of equation.
Coefficient with reactant and product:
P₄ 1
O₂ 5
P₂O₅ 2
There is no coefficient written before P₄ it means only one P₄ is present.
Answer:
A. it is the lowest at low temperatures
Explanation:
At low temperature the kinetic energy of a molecule is low. The kinetic energy is directly proportional to the temperature of the molecule. The kinetic energy of a molecule increases with the increase in the temperature that energize the molecules of a substance and makes them to move faster than before.
As the kinetic energy is proportional to temperature so it does not increase with decrease in the temperature (low temperature). The kinetic energy varies with the change in the temperature and it is not same at all temperature. The kinetic energy is highest at high temperature. Thus, option A is correct.
