Well, I know one. A positive: decreasing pollution because most people are in quarantine and not outside.
I this is really hard who can help me complete all of these because this is acknowledged
<u>Answer:</u> The volume of stock solution needed is 0.016 L
<u>Explanation:</u>
To calculate the volume of stock solution, we use the equation:

where,
are the molarity and volume of the stock solution
are the molarity and volume of diluted solution
We are given:

Putting values in above equation, we get:

Hence, the volume of stock solution needed is 0.016 L
<span>Fe atomic mass = 55.86
* 1 = 55.86
Cr atomic mass = 52
*2 = 104
O atomic mass = 16
* 4 = 64
Total molecular mass = 223.86
Percent by mass Fe = (55.86/223.86)*100 = 24.95%
Percent by mass Cr = 46.45%
Percent by mass O = 28.59%</span>