Answer:
1.635 M
Explanation:
Given:
10 mL of 20 volumes Hydrogen Peroxide
Here,
20 volumes of Hydrogen Peroxide means that on decomposition of 1 mL of H₂O₂ 20 mL of O₂ is obtained
also,
means 1 dm³ of H₂O₂ solution produces 20 dm³ oxygen
Now,
at 298K and 1 atm
20 dm³ oxygen = 
moles
or
= 0.817 moles
also,
2H₂O₂ → 2H₂O + O₂
thus,
1 dm³ of solution must contain 2 × moles of O₂ as moles of H₂O₂
thus,
Number of moles of H₂O₂ = 2 × 0.817
or
Number of moles of H₂O₂ = 1.635 moles
Hence,
For 20 volume hydrogen peroxide is 1.635 M
Explanation:
It is given that volume is 0.50 L and molarity is 0.485 M. Hence, number of millimoles will be calculated as follows.
Number of millimoles = Molarity × Volume
As there are 1000 mL in 1 L. So, 0.50 L equals 500 mL.
Therefore, putting the given values into the above formula as follows.
Number of millimoles = Molarity × Volume
= 0.485 M × 500 mL
= 242.5
Thus, we can conclude that 242.5 millimoles of copper(II) sulfate has been added by the chemist to the flask.
Answer:
d. 54.9 kPa
Explanation:
mmHg and Pa are units of pressure used in chemistry principally in the study of gases. 1mmHg is equal to 133.322Pa. 412mmHg are:
412 mmHg * (133.322Pa / 1mmHg) = 54929 Pa
The prefix K (Kilo) represents one thousand of the determined unit.
54929Pa are:
54929Pa * (1KPa / 1000Pa) = 54.9kPa
Right answer is:
<h3>d. 54.9 kPa
</h3>
