Chemistry, 18.03.2020 21:59 afifakiran5226
Phenolphthalein is an indicator that turns from colorless (acidic form) to magenta (basic form) and has a pKa of 9.40. What is the ratio of the magenta phenolphthalein concentration to the colorless phenolphthalein concentration ([magenta phenolphthalein]/[colorless phenolphthalein]) at a pH of 11?
Answers: 1
![pH=pK_a+\log(\frac{[salt]}{[acid]})](/tpl/images/0552/6240/e4eea.png)
![pH=pK_a+\log(\frac{[magenta(Php)]}{[Php]})](/tpl/images/0552/6240/ed1ee.png)
= negative logarithm of acid dissociation constant of phenolphthalein = 9.40![[magenta(Php)]](/tpl/images/0552/6240/398bf.png)
= concentration of magenta phenolphthalein![[Php]](/tpl/images/0552/6240/c3176.png)
= concentration of colorless phenolphthalein![11=9.40+\log(\frac{[magenta(Php)]}{[Php]})](/tpl/images/0552/6240/4797c.png)
![\log(\frac{[magenta(Php)]}{[Php]})=11-9.40=1.6](/tpl/images/0552/6240/3f9c3.png)
![\frac{[magenta(Php)]}{[Php]}=10^{1.6}=39.81 :1 \approx 40:1](/tpl/images/0552/6240/e1375.png)
Another question on Chemistry
Chemistry, 22.06.2019 03:00
In the 1800s, one of the statements in john dalton's atomic theory was that atoms are indivisible. later experimental evidence led to the discovery of subatomic particles such as neutrons, electrons, and protons. what happened to the indivisible atom part of dalton's atomic theory, and why?
Answers: 3
Chemistry, 22.06.2019 13:30
Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?
Answers: 3
Chemistry, 22.06.2019 13:50
What happens when an atom of sulfur combines with two atoms of chlorine to produce sci2? a. each chlorine atom shares a pair of electrons with the sulfur atom. b. an electron is transferred from each chlorine atom to the sulfur atom. c. an electron is transferred from the sulfur atom to each chlorine atom. d. each chlorine atom shares all its valence electrons with the sulfur atom.
Answers: 2
Chemistry, 22.06.2019 19:40
What is the wavelength of a 3*10^12 hz infrared wave a 3*10^20m b 1* 10^4m c 3*10^-3m d 1*10^-4 m
Answers: 1
You know the right answer?
Phenolphthalein is an indicator that turns from colorless (acidic form) to magenta (basic form) and...
Questions
Mathematics, 01.03.2020 01:49
Health, 01.03.2020 01:49
Biology, 01.03.2020 01:49
English, 01.03.2020 01:49
Mathematics, 01.03.2020 01:49
History, 01.03.2020 01:50
English, 01.03.2020 01:50
Mathematics, 01.03.2020 01:50
Mathematics, 01.03.2020 01:50
Mathematics, 01.03.2020 01:52
History, 01.03.2020 01:52
Mathematics, 01.03.2020 01:52
Geography, 01.03.2020 01:52
Mathematics, 01.03.2020 01:52
