Answer:
A
Explanation:
The answer A is the best answer because it contains the most general characteristic of a chemical change.
Answer:
8 moles
Explanation:
When we are asked to convert from grams of a substance into moles, we have to use the substance's molar mass.
Meaning that for this problem, we'll <em>use the molar mass of hydrogen peroxide</em> (H₂O₂), as follows:
There are 8 moles in 272 grams of hydrogen peroxide.
Let's solve ~
Initial concentration of weak acid HA = 0.200 M
and dissociation constant (
) is :
Now, at initial stage :
At equilibrium :
Now, we know :
![\qquad \sf \dashrightarrow \: { K_a = \dfrac{[H+] [A-]}{[HA]}}](https://tex.z-dn.net/?f=%5Cqquad%20%5Csf%20%20%5Cdashrightarrow%20%5C%3A%20%7B%20K_a%20%3D%20%5Cdfrac%7B%5BH%2B%5D%20%5BA-%5D%7D%7B%5BHA%5D%7D%7D%20)
( big brackets represents concentration )
Answer:3.
Explanation:when performing trace analyses and the analyte may adsorb to the glass.
Hey there!
Na + H₂O → NaOH + H₂
First, balance O.
One on the left, one on the right. Already balanced.
Next, balance H.
Two on the left, three on the right. Let's add a coefficient of 2 in front of NaOH and a coefficient of 2 in front of H₂O, so we have 4 on each side.
Na + 2H₂O → 2NaOH + H₂
Lastly, balance Na.
One on the left, two on the right. Add a coefficient of 2 in front of Na.
2Na + 2H₂O → 2NaOH + H₂
This is our final balanced equation.
Hope this helps!
