Given :
pH of solution of mixture of lactic acid and lactate is 4.26 .
To Find : ![log( \dfrac{[ \text{Conc. of lactate}]}{[\text{Conc . of lactic acid }]}) = 0.4](https://tex.z-dn.net/?f=log%28%20%5Cdfrac%7B%5B%20%5Ctext%7BConc.%20of%20lactate%7D%5D%7D%7B%5B%5Ctext%7BConc%20.%20of%20lactic%20acid%20%7D%5D%7D%29%20%20%3D%200.4)
The ratio of the lactate concentration to the lactate .
Solution :
We know , pKa of lactic acid is :
pKa = 3.86 .
Now , the solution of lactic acid and lactate is a buffer solution .
So , pHof buffer acid is given by :
![pH=pKa+log(\dfrac{[Salt]}{[Acid]})](https://tex.z-dn.net/?f=pH%3DpKa%2Blog%28%5Cdfrac%7B%5BSalt%5D%7D%7B%5BAcid%5D%7D%29)
Putting all given values :
Taking anti log both the sides , we get :
![\dfrac{[ \text{Conc. of lactate}]}{[\text{Conc . of lactic acid }]} = 2.51](https://tex.z-dn.net/?f=%5Cdfrac%7B%5B%20%5Ctext%7BConc.%20of%20lactate%7D%5D%7D%7B%5B%5Ctext%7BConc%20.%20of%20lactic%20acid%20%7D%5D%7D%20%20%3D%202.51)
Therefore , the ratio of the lactate concentration to the lactate is 2.51 .
Hence , this is the required solution .
The magnet's north pole would point to the Earth's south pole and the magnet's south pole would point to the Earth's north pole.
<u>Explanation</u>:
- There is a magnetic pole in the earth and the magnetic poles of the earth run using the equator and it has both the closures at the arctic pole and the Antarctic pole. The attractive positive field or the north pole is situated in the arctic zone and the south pole is situated in the Antarctic zone.
- The magnetic positive field or the north pole is situated in the arctic zone. Any magnet which is allowed to rotate whenever suspended on the outside of the earth will align itself with the magnetic field of the earth. That is the way the bar magnet orients itself comparative with this current planet's magnetic field.
I think the answer is D (number 4)
Yes and no he said that all atoms of a given element are identical in mass and properties.
