General Chemistry - Solutions & Intermolecular Forces (HW Help)

Click For Summary

Discussion Overview

The discussion revolves around a homework query related to general chemistry, specifically focusing on intermolecular forces, boiling points, and solutions. Participants are asked to evaluate multiple-choice questions regarding hydrogen bonding, boiling points of various compounds, and the behavior of a sucrose solution in equilibrium with solid sucrose.

Discussion Character

  • Homework-related
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Participants discuss which substances exhibit hydrogen bonding, with some suggesting that only option (c) CH3CH2-OH meets the criteria due to the presence of an electronegative atom (O) bonded to hydrogen.
  • There is a suggestion that the highest boiling point among the given options in question two might be (a) CF4, based on the assumption that hydrogen bonding is the strongest force, although others note that none of the options exhibit hydrogen bonding.
  • For question three, there is debate about the effect of adding solid sucrose to a solution in equilibrium, with some participants arguing that the concentration will increase while others suggest that the situation may lead to a supersaturated solution.
  • One participant emphasizes the importance of considering molecular mass and the nature of intermolecular forces (van der Waals forces) in determining boiling points.

Areas of Agreement / Disagreement

There is some agreement that option (c) is likely the correct answer for the first question regarding hydrogen bonding. However, for the second and third questions, multiple competing views remain, and the discussion does not reach a consensus on the correct answers.

Contextual Notes

Participants express uncertainty regarding the definitions and implications of hydrogen bonding and boiling points, as well as the behavior of solutions at equilibrium. The discussion highlights the complexity of these concepts without resolving the ambiguities present in the questions.

Who May Find This Useful

Students studying general chemistry, particularly those focusing on intermolecular forces, solutions, and boiling point concepts, may find this discussion relevant.

katrina007
Messages
47
Reaction score
0
Hi,

I need some help with my homework. I have three questions which I'm not quite sure which answer it is, though I give it my best try. If anyone can help, it'll be much appreciated. Thanks in advance...

Question One:
Which of the following substances will have hydrogen bonds between molecules?
a) (CH3)3N
b) CH3-O-CH3
c) CH3CH2-OH
d) CH3CH2-F
e) HI

** (e) can't be the answer becuz it doesn't have any Hydrogen Bonds (N,O,F)
** (a) can't be the answer becuz the N atom is by itself. H atom is attached to C atom and therefore can't bond with the N atom. Same with letter (d)

I think the answer is c... Plez correct me if I'm wrong.

Question Two:
Which of the following should have the highest boiling point?
a) CF4
b) CCl4
c) CBr4
d) CI4
e) CH4

** I think the answer if (a) becuz of the Hydrogen Bonding forces being the strongest of all forces and therefore has highest boiling point. Plez tell me know if this is the right answer or not and explain why - (if possible)

Question Three
A solution of Sucrose (sugar) in water in in equilibrium with solid sucrose. If more solid sucrose is now added, with stirring,
a) the concentration of the solution will increase
b) the concentration of the solution will decrease
c) the concentration of the solution will remain same
d) the volume of solution will increase
e) a supersaturated solution will be produced.

** (c) can't be the answer becuz something is being added so it has to change - cannot remain same. I took a guess on this one and I think its letter (a). Again please tell me if I am wrong or correct. and explain if possible.


Answers to anyone or all of these questions will be greatly appreciated. Need this 3 homework probs. done by tomorrow. Again, thanks in advance.

Regards,
Katrina
 
Physics news on Phys.org
Hello again,

Sorry to bump up this thread but please anyone out there that can help me with this 3 or anyone question(s)?
 
katrina007 said:
Hi,

I need some help with my homework. I have three questions which I'm not quite sure which answer it is, though I give it my best try. If anyone can help, it'll be much appreciated. Thanks in advance...

Question One:
Which of the following substances will have hydrogen bonds between molecules?
a) (CH3)3N
b) CH3-O-CH3
c) CH3CH2-OH
d) CH3CH2-F
e) HI

** (e) can't be the answer becuz it doesn't have any Hydrogen Bonds (N,O,F)
** (a) can't be the answer becuz the N atom is by itself. H atom is attached to C atom and therefore can't bond with the N atom. Same with letter (d)

I think the answer is c... Plez correct me if I'm wrong.

Question Two:
Which of the following should have the highest boiling point?
a) CF4
b) CCl4
c) CBr4
d) CI4
e) CH4

** I think the answer if (a) becuz of the Hydrogen Bonding forces being the strongest of all forces and therefore has highest boiling point. Plez tell me know if this is the right answer or not and explain why - (if possible)

Question Three
A solution of Sucrose (sugar) in water in in equilibrium with solid sucrose. If more solid sucrose is now added, with stirring,
a) the concentration of the solution will increase
b) the concentration of the solution will decrease
c) the concentration of the solution will remain same
d) the volume of solution will increase
e) a supersaturated solution will be produced.

** (c) can't be the answer becuz something is being added so it has to change - cannot remain same. I took a guess on this one and I think its letter (a). Again please tell me if I am wrong or correct. and explain if possible.


Answers to anyone or all of these questions will be greatly appreciated. Need this 3 homework probs. done by tomorrow. Again, thanks in advance.

Regards,
Katrina

I agree that the best answer for #1 seems like C. Requirement for H bonding is that there's an electronegative atom (NOF) and a H bonded to an electronegative atom... so only answer choice C has an electronegative atom (O) and a hydrogen bonded to an electronegative atom (in the OH group)
 
And for #3, if I understood the question correctly, looking at the definition of supersaturated solution may help:

http://www.chem.purdue.edu/gchelp/gloss/supersatsoln.html

supersaturated solution: a solution that contains more solute than it would if the dissolved solute were in equilibrium with the undissolved solute
 
2: think molecular mass. 3: "equilibrium with solid sucrose" --- think, what color is George Washington's white horse?
 
btw, for #2, in the given answer choices, there's no hydrogen bonding present.
 
#2 the molecules are neither polar nnor possesses hydrogen bonding... van der waal forces exist as attractive forces between them...

what does the strength of van der waal forces depend on?? from this you will be able to determine the substance with higher bp...
 

Similar threads

Chemistry Intermolecular Bonding of CH4: Van der Waals
  • · Replies 5 ·
Replies
5
Views
3K
Polarizability: Understanding its Effects on Intermolecular Forces in Chemistry
  • · Replies 1 ·
Replies
1
Views
4K
Chemistry General Chemistry - Intermolecular Forces
  • · Replies 1 ·
Replies
1
Views
10K
Chemistry Finding the molecular formula of an unknown hydrocarbon
  • · Replies 4 ·
Replies
4
Views
3K
Chemistry What Intermolecular Forces Operate in H₂O and CH₃OH Liquids?
  • · Replies 9 ·
Replies
9
Views
5K
Chemistry Which Intermolecular Forces Affect These Organic Compounds?
  • · Replies 5 ·
Replies
5
Views
4K
Which Compound Has Highest Boiling Point?
  • · Replies 3 ·
Replies
3
Views
2K
Chemistry Boiling Points and Intermolecular Forces
  • · Replies 1 ·
Replies
1
Views
3K
Chemistry Chemistry-Physical Changes and Intermolecular Forces
  • · Replies 2 ·
Replies
2
Views
6K
Sublimation of Graphite: Understanding the Process and Its Significance
  • · Replies 2 ·
Replies
2
Views
3K