Answer : The concentration of
ion is, 
Solution : Given,
pH = 4.20
First we have to calculate the pOH.
As we know that,




Now we have to calculate the concentration of
ion.
![pOH=-\log [OH^-]](https://tex.z-dn.net/?f=pOH%3D-%5Clog%20%5BOH%5E-%5D)
![9.8=-\log [OH^-]](https://tex.z-dn.net/?f=9.8%3D-%5Clog%20%5BOH%5E-%5D)
![[OH^-]=1.58\times 10^{-10}M](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D1.58%5Ctimes%2010%5E%7B-10%7DM)
Therefore, the concentration of
ion is, 
To measure the electrolytes in this science project, you will use a multimeter. A multimeter is an electronic device that measures voltage, current, and resistance. You can learn more about these terms in the Science Buddies Electronics Primer.
Answer:
b) pH = 9.25
Explanation:
- NH4+(aq) + H2O(l) ↔ NH3(aq) + H3O+(aq)
- NH3 + H2O ↔ NH4+ + OH-
- 2 H2O ↔ H3O+ + OH-
⇒ Kb = [ NH4+ ] * [ OH- ] / [ NH3 ] = 1.86 E-5......from literature
mass balance NH4+:
⇒ M NH4+ = [ NH4+ ] - [ OH- ]
∴ [ NH3 ] ≅ M NH4+ = 0.26 M
⇒ Kb = (( 0.26 + [ OH- ] )) * [ OH- ] / 0.26 = 1.86 E-5
⇒ 0.26 [ OH-] + [ OH- ]² = 4.836 E-6
⇒ [ OH- ]² + 0.26 [ OH- ] - 4.836 E-6 = 0
⇒ [ OH- ] = 1.859 E-5 M
⇒ pOH = - Log ( 1.859 E-5 )
⇒ pOH = 4.7305
⇒ pH = 14 - pOH = 9.269
The correct balanced equation of a beta decay undergone by Mercury-203 is as follows:
203 80 Hg → 203 81 + 0 -1 e
<h3>What is beta decay?</h3>
Beta decay in radioactivity refers to the release of a beta particle by a radioactive element.
Beta particle is characterized by the possession of mass number 0 and atomic number -1.
This means that if Mercury-203 undergoes beta decay, the atomic number of the resulting isotope will be +1 as follows:
203 80 Hg → 203 81 Tl + 0 -1 e
Learn more about beta radiation at: brainly.com/question/1580990