Answer:
37 mmol of acetate need to add to this solution.
Explanation:
Acetic acid is an weak acid. According to Henderson-Hasselbalch equation for a buffer consist of weak acid (acetic acid) and its conjugate base (acetate)-
![pH=pK_{a}(acetic acid)+log[\frac{mmol of CH_{3}COO^{-}}{mmol of CH_{3}COOH }]](https://tex.z-dn.net/?f=pH%3DpK_%7Ba%7D%28acetic%20acid%29%2Blog%5B%5Cfrac%7Bmmol%20of%20CH_%7B3%7DCOO%5E%7B-%7D%7D%7Bmmol%20of%20CH_%7B3%7DCOOH%20%7D%5D)
Here pH is 5.31, 
(acetic acid) is 4.74 and number of mmol of acetic acid is 10 mmol.
Plug in all the values in the above equation:
![5.31=4.74+log[\frac{mmol of CH_{3}COO^{-}}{10}]](https://tex.z-dn.net/?f=5.31%3D4.74%2Blog%5B%5Cfrac%7Bmmol%20of%20CH_%7B3%7DCOO%5E%7B-%7D%7D%7B10%7D%5D)
or, mmol of 
= 37
So 37 mmol of acetate need to add to this solution.
Answer:
Option D: More than 30 seconds
Explanation:
The enzyme CATALASE is found in almost all living organisms. CATALASE helps in the decomposition of one substance into another substance. CATALASE will breaks down hydrogen peroxide into water and oxygen.
When the potatoes were boiled it will surely produce no bubbles because the heat would have degrade the enzyme - catalase While the potatoes at room temperature potato produced the most bubbles because catalase works best at a room temperature.
If the potato solution was boiled for 10 minutes and cooled for 10 minutes before being tested, the average time for the disks to float to the surface of the hydrogen peroxide solution would be MORE THAN 30 SECONDS
Alpha particles are helium nucleus ! so answer is A !
it is made by ionization of helium, when both the electrons are out , then two unit of positive charge is one helium and thus called alpha particle !
Explanation:
The above two reactions xcan also be written in form of single chemcial equation:
![FeCl_3+K(SCN)\rightleftharpoons KCl+[Fe(SCN)]Cl_2(blood-red)](https://tex.z-dn.net/?f=FeCl_3%2BK%28SCN%29%5Crightleftharpoons%20KCl%2B%5BFe%28SCN%29%5DCl_2%28blood-red%29)
1. Color of ferric chloride solution is yellow. This is due to presence of ferric ions which have yellow color in their aqueous solutions.
2. KSCN has the colorless solution. This due to potassium ion forms colorless aqueous solution.
3. On mixing, KSCN with 
we will get blood red color solution of ![[FeSCN]Cl_2](https://tex.z-dn.net/?f=%5BFeSCN%5DCl_2)
.
The answer is A i did this before hope this helps
