Students were enquired to answer a question at institution and to mention what is most important for them to succeed. One which response stood out from the rest was practice. Successful people are generally not born successful; they become successful through hard work and perseverance. This is how you can obtain your goals. These are some question and answer examples that you could definitely implement to elevate your knowledge and gain insight that will guide you to keep up your school studies.
Question:
1 Which best defines concentration?A ratio that describes the amount of solute divided by the amount of solvent or solution
B ratio that describes the amount of solvent or solution divided by the amount of solute
C ratio that describes the mass of solute divided by the mass of solvent
D ratio that describes the amount of solvent in a solution
2 Which contributes to the dissolution of sugar in water?
A the dissociation of an ionic compound in water
B a strong pull of water molecules on an ionic compound
C the dissociation of a polar covalent compound in water
D a strong pull of water molecules on a polar covalent compound
Answer:
These are two questions and two answers.
Question 1: Which best defines concentration?
Answer: option A, ratio that describes the amount of solute divided by the amount of solvent or solution
Explanation:
There are many different measures of concentration: percent, molarity, molality, mole fraction are some examples.
All of them express the ratio of solute to solvent or solution, in different kind of units, may be mass, number of moles, or volume.
Molarity is number of moles of solute per liter of solution. Molality is number of moles of solute per kg of solvent.
So, as you see it is always a ratio of the amound of solute, but it is not a fixed unit.
Question 2. Which contributes to the dissolution of sugar in water?
Answer: option D, a strong pull of water molecules on a polar covalent compound.
Sugar is not a ionic compound so it does not dissociate.
Sugar is a molecule, so it remains as such in solution.
Sugar is polar, so it can be dissolved in water that is a polar solvent (like dissolve like, is the rule).
The dissolution is explained by the fact that the pull exerted by the molecultes of solvent on the molecules of solute, is greater than the pull that the molecules of solute extert among themselves.
That permits the molecules of solvent surround the molecules of solute and get them appart of the solid substance to form the aqueous solution.
From the answer and question examples above, hopefully, they are able to guide the student sort out the question they had been looking for and take notice of all things stated in the answer above. Then could certainly make some sharing in a group discussion and also learning with the classmate in connection with the topic, so another student also absorb some enlightenment and still keeps up the school learning.