Answer:
16
Explanation:
number of electrons should also be 16.
Because the moon gets between the Sun and the Earth so you can't see the moon
Answer:
The final dilution is 1:400
Explanation:
Let's analyze what we are told: we have an initial 1:5 dilution of protein lysate. This means that the initial solution (stock solution) was diluted 5 times. Then, from this dilution the student prepared another dilution taking 2 mL of the first dilution in 8 mL of water. This is the same as saying we took 1 mL of first dilution in 4 mL of water (the ratio is the same), so we now have a second 1:4 dilution of the first dilution (1:5). Finally, the student made a third 1:20 dilution, this means that the second dilution was further diluted 20 times.
So, to calculate the final dilution of protein lysate, we have to multiply all the dilution factors of every dilution prepared: in this case we have a final dilution of 1:20, this means we have a factor dilution of 20. But it was previously diluted 4 times, so we have a factor dilution of 20×4 = 80. However, this dilution was also previously diluted 5 times, so the new dilution factor is 80 × 5 = 400
This means that the final dilution of the compound was diluted a total of 400 times compared to the initial concentration of stock solution.
Explanation:
We have to calculate 
value.
It is known that at the equivalence point concentration of acid is equal to the concentration of anion formed.
Hence, [HA] = ![[A^{-}]](https://tex.z-dn.net/?f=%5BA%5E%7B-%7D%5D)
Now, relation between and pH is as follows.
pH = ![pK_{a} + log \frac{[A^{-}]}{[HA]}](https://tex.z-dn.net/?f=pK_%7Ba%7D%20%2B%20log%20%5Cfrac%7B%5BA%5E%7B-%7D%5D%7D%7B%5BHA%5D%7D)
Putting the values into the above formula as follows.
pH =
4.23 = 
(as [HA] = )
= 4.23 (as log (1) = 0)
or, = 4
Thus, we can conclude that of given weak acid is 4.
It’s a neutrons and electrons
