Answer:
![\frac{[magenta\ phenolphthalein]}{[colorless\ phenolphthalein]}=31.62](https://tex.z-dn.net/?f=%5Cfrac%7B%5Bmagenta%5C%20phenolphthalein%5D%7D%7B%5Bcolorless%5C%20phenolphthalein%5D%7D%3D31.62)
Explanation:
Considering the Henderson- Hasselbalch equation for the calculation of the pH of the buffer solution as:
![pH=pKa+\log\frac{[base]}{[acid]}](https://tex.z-dn.net/?f=pH%3DpKa%2B%5Clog%5Cfrac%7B%5Bbase%5D%7D%7B%5Bacid%5D%7D)
Where Ka is the dissociation constant of the acid.
pKa of phenolphthalein = 9.40
pH = 10.9
So,
![10.9=9.40+\log\frac{[magenta\ phenolphthalein]}{[colorless\ phenolphthalein]}](https://tex.z-dn.net/?f=10.9%3D9.40%2B%5Clog%5Cfrac%7B%5Bmagenta%5C%20phenolphthalein%5D%7D%7B%5Bcolorless%5C%20phenolphthalein%5D%7D)
4.) an element cannot be decomposed by a chemical change, it is a pure substance and no other materials compose it.
Answer:
C = (5/9) F - (160/9)
They both read equal at Z = - 40
Explanation:
We are looking for a linear function so we can write the following condition
Y = aX + b
Applying it to the exercise we got C = a F + b
Let's use the facts that C = 0 when F = 32 and C = 100 when F = 212
0 = 32 a + b (1)
100 = 212 a + b (2)
From (1) b = - 32 a , when we replace this in (2) we obtain a = (5/9)
and b = - (5/9)32 = - 160/9
Finally the linear function is C = (5/9) F - (160/9)
Both readings are equal at a Z number so
Z = (5/9) Z - 160/9
(4/9) Z = -160/9 and Z = - 40
Answer:
protons and neutrons are found in nucleus
