<h2>Answer : Option C) Joseph is observing the color of the reaction mixture to see whether proteins are present in the given solution.</h2><h3>Explanation :</h3>
An example of qualitative observation is the one where one uses the five senses to identify the changes in the reaction.
Here, when Joseph is studying a reaction mixture he is trying to observe a color change which will confirm that there is proteins present in the reaction mixture or not If there is a color change observed then it will confirm the presence of proteins.
Usually qualitative observations are those which can be easily predicted by using five senses.
Answer:
Solution A: crenation
Solution B: hemolysis
Solution C: hemolysis
Solution D: crenation
Solution E: crenation
Explanation:
Hemolysis is the rupturing of red blood cells, which results in the release of hemoglobin (from within the red blood cells) into the plasma. If a red blood cell is placed in a hypotonic solution, water will flow into the cell, the cell will swell and hemolysis will.
Crenation: when a red blood cell is placed in a <em>hypertonic solution (</em>such as highly saline solution), the red blood cell will lose water(osmosis) and will shrink in size. The red blood cell has undergone crenation.
In order for a red blood cell to prevent from undergoing hemolysis or crenation, the cell must be placed in an<em> isotonic solution, </em>i.e either in <u>0.9% (m/v) NaCl solution</u> or <u>5% glucose solution</u>
- Solution B and Solution C are hypotonic solution, thus red blood cell has undergone hemolysis.
- Solution A, D and E are hypertonic solution. thus red blood cell has undergone crenation
They are isotopes because isotopes have the same number of protons (atomic number) but can have different numbers of neutrons + protons (atomic mass).
2K + Cl₂ ⇒ 2KCl
2Ca + O₂ ⇒ 2CaO
