Answer & Explanation:
- The neutralization of H₂SO₄ with NaOH is occurred according to the balanced equation:
<em>H₂SO₄ + 2NaOH → Na₂SO₄ + 2H₂O,</em>
It is clear that every 1.0 mol of H₂SO₄ needs 2 mol of NaOH to be neutralized completely.
<em>So, when you mix one mole of sulfuric acid with 1 mole of sodium hydroxide, there will be an excess of sulfuric acid.</em>
<em>Thus, the pH of the solution remain below 7.</em>
Answer:
0.01836 M
Explanation:
Again the reaction equation is;
Fe(s) + Mn2+(aq) → Fe2+(aq) + Mn(s)
E°cell= 0.77 V
Ecell= 0.78 V
[Mn2+] = 0.040 M
[Fe2+] = the unknown
n=2
From Nernst's equation;
Ecell= E°cell- 0.0592/n log Q
0.78= 0.77 - 0.0592/2 log [Fe2+] /[0.040]
0.78-0.77= - 0.0592/2 log [Fe2+] /[0.040]
0.01/ -0.0296= log [Fe2+] /[0.040]
-0.3378= log [Fe2+] /[0.040]
Antilog(-0.3378) = [Fe2+] /[0.040]
0.459= [Fe2+] /[0.040]
[Fe2+] = 0.459 × 0.040
[Fe2+] = 0.01836 M
Answer:
the unknown substance is a protein
Explanation:
The biuret test is one of the tests for proteins. It can be used to detect peptide linkages. The biuret test is carried out in an alkaline solution. A coordination complex is formed leading to the appearance of a violet color.
Summarily, the biuret method is a colorimetric technique used to test for proteins and peptides. It involves the formation of a purple (violet) complex of Copper salts in alkaline solution.
Hence when the biuret reagent is added to an unknown substance and it turns purple, the unknown substance is a protein
Answer:
sulphuric is a strong acid
Explanation:
Sulphuric is a strong acid because it completely ionises in water while acetic acid partially ionises in water