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
The mass of sodium sulphate, Na₂SO₄, required to prepare the solution is 10.65 g
<h3>How to determine the mole of sodium sulphate Na₂SO₄</h3>
- Volume = 250 mL = 250 / 1000 = 0.25 L
- Molarity = 0.3 M
Mole = Molarity x Volume
Mole of Na₂SO₄ = 0.3 × 0.25
Mole of Na₂SO₄ = 0.075 mole
<h3>How to determine the mass of sodium sulphate Na₂SO₄</h3>
- Molar mass of Na₂SO₄ = 142.05 g/mol
- Mole of Na₂SO₄ = 0.075 mole
Mass = mole × molar mass
Mass of Na₂SO₄ = 0.075 × 142.05
Mass of Na₂SO₄ = 10.65 g
Thus, 10.65 g of Na₂SO₄ is needed to prepare the solution.
Learn more about molarity:
brainly.com/question/15370276
Answer:
N-terminal Phe, C-terminal Ser
Explanation:
Amino acids connect like
NH2 -CH(R1) -CO -NH-CH(R2)-CO-.....-NH-CH(Rn)COOH
So, 1st amino acid is N -terminal , and it is Phe.
Last amino acid is C- terminal, and it is Ser.
There are many safety precautions and rules you MUST follow during labs.
for this incident here is what you should do:
1)Notify your Instructor and partner
2) if the liquid is toxic (like not water or vinegar) then let your Instructor handle it properly, or follow your instructors orders (like if they say to put a towel over it or something like that)
3) Broken glassware, minus mercury thermometer, must be immediately cleaned up, do not use your bare hand, always wear gloves.
4)dispose of the broken glass properly and clean the liquid up (unless it is harmful, then let your instructor do it)
