Answer:
Explanation:
Toe change the retention factor of a TLC analysis, you can change your solvent for a more or less polar one, depending on your analyte. You can use a mix of solvents too.
You can also change the your method to visualize the spots, you can use fluorescent compounds that can only be seen in black light, you can use Iodine, Bromine and so on.
Answer:
True.
Explanation:
Iodine is an essential element required for the synthesis of Thyroxine is a correct statement.
Iodine is an essential and controlling medium for thyroid hormone production, as a minor ingredient. It is an important element in the development of thyroid hormones thyroxine (T4) and triiodothyronine (T3) by the thyroid gland.
Answer:
sublimation
Explanation:
solid => liquid Melting
liquid => solid freezing
liquid => gas evaporation
gas => liquid condensation
solid => gas sublimation
gas => solid deposition (e.g.; formation of frost), however some scholars will also refer to this process as sublimation.
Answer:
1.7 mL
Explanation:
<em>A chemist must prepare 550.0 mL of hydrochloric acid solution with a pH of 1.60 at 25 °C. He will do this in three steps: Fill a 550.0 mL volumetric flask about halfway with distilled water. Measure out a small volume of concentrated (8.0 M) stock hydrochloric acid solution and add it to the flask. Fill the flask to the mark with distilled water. Calculate the volume of concentrated hydrochloric acid that the chemist must measure out in the second step. Round your answer to 2 significant digits.</em>
Step 1: Calculate [H⁺] in the dilute solution
We will use the following expresion.
pH = -log [H⁺]
[H⁺] = antilog - pH = antilog -1.60 = 0.0251 M
Since HCl is a strong monoprotic acid, the concentration of HCl in the dilute solution is 0.0251 M.
Step 2: Calculate the volume of the concentrated HCl solution
We want to prepare 550.0 mL of a 0.0251 M HCl solution. We can calculate the volume of the 8.0 M solution using the dilution rule.
C₁ × V₁ = C₂ × V₂
V₁ = C₂ × V₂/C₁
V₁ = 0.0251 M × 550.0 mL/8.0 M = 1.7 mL
