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:
A:UNDERSTANDING CONCEPTS PART A 13) Which of the following is an example of periodicity? A) eating breakfast
Answer:
A. It is the work done when a force of 1 newton is applied to an object for a distance of 1 meter
Explanation:
Missing question: <span>A 5.00 L sample of O2 at a given temperature and pressure contains a 1.08x10^23 molecules. How many molecules would be contained in each of the following at the same temperature and pressure? </span>
a) 5.00 L H2.
<span>b) 5.00 L CO2.
Use </span>Avogadro's Law: The Volume Amount Law: <span>equal </span>volumes<span> of all gases, at the same temperature and pressure, have the same </span>number<span> of molecules. Because hydrogen and carbon(IV) oxide are gases, number of molecules are the same as number of oxygen molecules, so:
a) N(H</span>₂) = 1.08·10²³.
b) N(CO₂) = 1.08·10²³