<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.
CO2, C2H2, BeF2, XeF2, etc all these molecules have linear geometry.
Answer:
A, C and D are correct.
Explanation:
Hello.
In this case, since the relationship between the vapor pressure of a solution is directly proportional to the mole fraction of the solvent and the vapor pressure of the pure solvent as stated by the Raoult's law:

Since the solute is not volatile, the mole fraction of the solute is not taken into account for vapor pressure of the solution, therefore A is correct whereas B is incorrect.
Moreover, since the higher the vapor pressure, the weaker the intermolecular forces due to the fact that less more molecules are like to change from liquid to vapor and therefore more energy is required for such change, we can evidence that both C and D are correct.
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<h3><u>Answer;</u></h3>
Phloem
<h3><u>Explanation;</u></h3>
- <u>Club moss</u> plant belongs to the the family Lycopodiaceae, Lycophyte includes any spore-bearing vascular plant.
- <u>Liverworts</u> on the other hand are bryophytes which belongs to the division bryophyta. Bryophytes are small, non-vascular plants which includes mosses, hornworts and liverworts.
- <em><u>Vascular plants contain vascular tissues which play an important role of transportation in plants. </u></em>The major vascular tissues are phloem and xylem. <em><u>Non-vascular plants</u></em> on the other hand lacks the vascular tissues for transportation of substances.