"S<span>cientists believe that solids are mostly open space" is the statement among the statements given in the question that is true. The correct option among all the options that are given in the question is the second option or option "B". I hope that this answer has actually come to your help.</span>
To determine the amount of heat needed to evaporate a certain amount of water at its boiling point, we use the equation,
H = m(Hv)
where H is the heat, m is the mass (in grams), and Hv is the latent heat of vaporization. Substituting the known values,
H = (105 g)(540 cal/g)
H = 56700 cal
H = 56.7 kcal
Answer: 56.7 kcal
3 CuSO4(aq)+2Al(s) -->Al2(SO4)3(aq)+Cu(s) is a
balanced equation for Copper (II) sulfate + aluminum --> aluminum
sulfate+solid copper. The correct answer between all the choices
given is the second choice or letter B. I am hoping that this answer has
satisfied your query and it will be able to help you in your endeavor, and if
you would like, feel free to ask another question.
Answer:
pH= 11.5
Explanation:
To the calculation of the <u>pH value</u>, we need to write the ionization equation first. Then using the <u>ICE table</u> and the information given by the problem we can set up the problem:
I 1.1 M Zero Zero
C -X +X +X
E 1.1-X X X
As next step, using the <u>equilibrium expression</u> for Kb we can replace the terms find in the ICE table and then <u>solve for X</u>, so:
![Kb=\frac{[C_4H_4N_2O_3NH_3^+][OH^-]}{[C_4H_4N_3O_3NH_2]}](https://tex.z-dn.net/?f=Kb%3D%5Cfrac%7B%5BC_4H_4N_2O_3NH_3%5E%2B%5D%5BOH%5E-%5D%7D%7B%5BC_4H_4N_3O_3NH_2%5D%7D)
![9.2x10^-^6=\frac{[X][X]}{[1.1-X]}](https://tex.z-dn.net/?f=9.2x10%5E-%5E6%3D%5Cfrac%7B%5BX%5D%5BX%5D%7D%7B%5B1.1-X%5D%7D)
![(9.2x10^-^6)*[1.1-X]=X^2](https://tex.z-dn.net/?f=%289.2x10%5E-%5E6%29%2A%5B1.1-X%5D%3DX%5E2)
With the value of X we can find the <u>pOH</u> (lets remember that X<u> is the concentration of OH-</u>), so:
Finally, we can find the <u>pH value</u> with the equation:
<u>The 1.1 M allantoin solution have a pH value of 11.5</u>
