PKa= 4.9 therefore ka= 10^-4.9= 1.259x10^-5
![ka= \frac{[H^+][CH3CH2COO^-]}{[CH3CH2COOH]}](https://tex.z-dn.net/?f=ka%3D%20%5Cfrac%7B%5BH%5E%2B%5D%5BCH3CH2COO%5E-%5D%7D%7B%5BCH3CH2COOH%5D%7D%20)
![[CH3CH2COO^-] ](https://tex.z-dn.net/?f=%5BCH3CH2COO%5E-%5D%0A)
= 0.05
![[CH3CH2COOH]](https://tex.z-dn.net/?f=%5BCH3CH2COOH%5D)
= 0.10
Therefore 1.259x10^-5 =
![\frac{[H^+][0.05]}{[0.1]}](https://tex.z-dn.net/?f=%20%5Cfrac%7B%5BH%5E%2B%5D%5B0.05%5D%7D%7B%5B0.1%5D%7D%20)
Rearrange the equation to make the concentration of hydrogen the subject.
Therefore
![[H^+] = \frac{(1.259*10^-5)(0.1)}{0.05}](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%20%3D%20%20%5Cfrac%7B%281.259%2A10%5E-5%29%280.1%29%7D%7B0.05%7D%20%20)
Therefore
![[H^+]= 2.513*10^-5](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D%202.513%2A10%5E-5)
pH= -log [
] = -log(2.513*10^-5)= 4.59.
Explanation:
1) Based on the octet rule, iodine form an <u>I</u>⁻ ion.
Therefore,
Option E is correct ✔
2) The electronic configuration of the sulfide ion (S²⁻) is :
₁₆S = 1s² 2s² 2p⁶ 3s² 3p⁴ or [Ne] 3s² 3p⁴
₁₈S²⁻ = 1s² 2s² 2p⁶ 3s² 3p⁶ or [Ne] 3s² 3p⁶
Therefore,
Option E is correct ✔
3) valence shell electron of
Halogens = 7
Alkali metal = 1
Alkaline earth metal = 2
Therefore,
Option D is correct ✔
4) Group 2 element lose two electron in order to achieve Noble gas configuration.
And here Group 2 element is Sr
Therefore,
Option B is correct ✔
5) Group 13 element lose three electron in order to achieve Noble gas configuration.
And here Group 13 element is Al
Therefore,
Option B is correct ✔
6) For a given arrangements of ions, the lattice energy increases as ionic radius <u>decreases</u> and as ionic charge <u>increases</u>.
Therefore,
Option A is correct ✔
IBM and others are using copper instead of aluminum in the most powerful computer chips they manufacture. Because of copper's superior electrical conductivity, this technology enables conductor channel lengths and widths to be significantly reduced.
Metals don't form covalent bonds because of the low ionization energes of the metal atoms. It is easier for them to release electrons rather than sharing it. But this is not always the case, there are some metals that can form covalent bonds.
Answer:
[α] = -77.5° / 
Explanation:
Given;
Mass of optically pure substance in the solution = 10 g
Volume of water = 500 mL
Length of the polarimeter, l = 20 cm = 20 × 0.1 dm = 2 dm
measured rotation = - 3.10°
Now,
The specific rotation ( [α] ) is given as:
[α] = 
here,
α is the measured rotation = -3.10°
c is the concentration
or
c = 
or
c = 
or
c = 0.02 g/mL
on substituting the values, we get
[α] = 
or
[α] = -77.5° /
