Answer:
0.159 \%
Explanation:
The acid will dissociate according to the reaction shown below:-
![RCOOH + H_2O\rightleftharpoons RCOO^- + H_3O^+](https://tex.z-dn.net/?f=RCOOH%20%2B%20H_2O%5Crightleftharpoons%20RCOO%5E-%20%2B%20H_3O%5E%2B)
Given that, pH=3.8
The concentration of can be determined from the expression fo pH as:-
pH = - log ![[H^+]](https://tex.z-dn.net/?f=%5BH%5E%2B%5D)
3.8 = - log ![[H^+]](https://tex.z-dn.net/?f=%5BH%5E%2B%5D)
= ![1.59\times 10^{-4}\ M](https://tex.z-dn.net/?f=1.59%5Ctimes%2010%5E%7B-4%7D%5C%20M)
The initial concentration of RCOOH was 0.10 M, then the percent dissociation was- calculated as shown below:-
![\% \ dissociation=\frac{1.59\times 10^{-4}}{0.10}\times 100=0.159\ \%](https://tex.z-dn.net/?f=%5C%25%20%5C%20dissociation%3D%5Cfrac%7B1.59%5Ctimes%2010%5E%7B-4%7D%7D%7B0.10%7D%5Ctimes%20100%3D0.159%5C%20%5C%25)
Answer:
Li2S> Na2S> K2S> CsS
Explanation:
The lattice energy of ionic species depends on the relative sizes of ions in the ionic compounds. As the size of ions increases, the lattice energy decreases and vice versa.
When the size of the anions are the same, the lattice energy now depends on the relative sizes of the cations. Therefore, since all the compounds are sulphides and the order of magnitude of ionic sizes is: Li^+ < Na^+ < K^+ < Cs^+.
Therefore, the order of decrease in lattice energy is; Li2S> Na2S> K2S> CsS
Answer:
They are composed of hydrogen and helium
The ideal gas law is: PV=nRT
Pressure
Volume
n= moles
R= gas constant
Temperature in Kelvin
(Degrees in celsius +273)
n= PV/RT
(1.00atm)(5.00L)/(.08026)(295K)= .207mol of gas