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: the reliability will be worse
Explanation:
Suppose we used 0.5 M NaOH to titrate our vinegar sample instead of 0.1 M.
Now by using 0.5M instead of 0.1M we are increasing the concentration of NaOH,
We know that the moles used = Volume x concnetration.
so for the same no of moles, if the concentration increases, the volume decreases.
Hence it will consume less NaOH.
now Since the volume decreases, the titration volume of less number will increase the % error.
Therefore the reliability will be worse.
Its charge would be the amount of electrons that are lost in total, which the information is not stated
Answer:
"Hydrogen is still available outside the core, so hydrogen fusion continues in a shell surrounding the core. The increasingly hot core also pushes the outer layers of the star outward, causing them to expand and cool, transforming the star into a red giant."
