Chemistry-Physical Changes and Intermolecular Forces

In summary, the conversation discusses the relationship between Intermolecular Forces and physical changes, specifically the boiling point. The individual is a beginner in studying chemistry and asks questions about the amount of energy needed to change the state of matter and how to calculate boiling point between different molecules. They also ask for clarification on which molecule has the highest boiling point among H2O, CO2, CH4, Kr, and NH3, and whether the number of hydrogen bonds and electronegativity affect the boiling point. The expert summarizer concludes that H2O and NH3 have the highest boiling points due to their hydrogen bonds and that Oxygen has a higher electronegativity than Nitrogen.
  • #1
Flip
8
0
Hi everyone.

I have recently just started studying chemistry for my Junior year in High School. So you could say that I am a newbie at this. :smile:

I have small knowledge on the relationship between Intermolecular Forces and Physical changes. (Example: Boiling Point.)

So if the IMF of a molecule is high, would it take more energy(heat) to move it to a different state of matter? And if so how would the amount of energy be determined? How do you calculate the boiling point between 3 molecules?

Example:

46. Of the following substances,_____________ has the highest boiling point. (All numbers in the bottom are sub-scripts)

H20
CO2
CH4
Kr
NH3

A)H2O
B)CO2
C)CH4
D)Kr
E)NH3

Since H2O and NH3 have Hydrogen bonds I would assume that both those elements have the highest boiling points. Would more hydrogen atoms bonded on to the central atom mean that that molecule has the highest boiling point? If so then does that mean NH3 has the highest boiling point?
 
Last edited:
Physics news on Phys.org
  • #2
Does NH3 have a more hydrogen bond connections with respect to the individual molecule in an intermolecular "network." Also, which one has a higher electronegativity, Oxygen or Nitrogen?
 
  • #3
Oxygen is more electronegative.
 

Related to Chemistry-Physical Changes and Intermolecular Forces

1. What is the difference between a physical change and a chemical change?

A physical change refers to a change in the physical properties of a substance, such as its shape, size, or state of matter, without altering its chemical composition. On the other hand, a chemical change involves a rearrangement of the atoms in a substance, resulting in the formation of new substances with different chemical properties.

2. How do intermolecular forces affect the properties of a substance?

Intermolecular forces are the attractive forces between molecules, and they play a crucial role in determining the physical properties of a substance. These forces can affect the boiling and melting points, viscosity, and solubility of a substance.

3. What are the different types of intermolecular forces?

The three main types of intermolecular forces are London dispersion forces, dipole-dipole interactions, and hydrogen bonding. London dispersion forces are the weakest of these forces and occur between all molecules. Dipole-dipole interactions are stronger and occur between polar molecules. Hydrogen bonding is the strongest intermolecular force and occurs between molecules containing hydrogen bonded to a highly electronegative atom.

4. How can intermolecular forces be affected by temperature and pressure?

As temperature and pressure increase, the kinetic energy of the molecules also increases, causing them to move faster and overcome the intermolecular forces holding them together. This can lead to a change in the physical state of a substance, such as melting or boiling. Additionally, higher pressures can also affect the spacing between molecules, altering the strength of intermolecular forces.

5. How do physical changes affect the intermolecular forces between molecules?

Physical changes, such as changes in temperature or pressure, can disrupt the balance of intermolecular forces between molecules. For example, increasing the temperature can weaken intermolecular forces, leading to a change in physical state. Similarly, applying pressure can cause molecules to come closer together, increasing the strength of intermolecular forces between them.

Similar threads

Chemistry: Heat of Sublimation and Hydrogem Bonds Problem
    • Biology and Chemistry Homework Help
Replies
5
Views
1K
Which substance has the highest boiling point?
    • Biology and Chemistry Homework Help
Replies
4
Views
11K
Polarizability: Understanding its Effects on Intermolecular Forces in Chemistry
    • Biology and Chemistry Homework Help
Replies
1
Views
3K
Highest boiling point between organic compounds
    • Biology and Chemistry Homework Help
Replies
2
Views
2K
Chemistry How do we know ##BF_3## has Lewis structure but ##Al_2S_3## does not?
    • Biology and Chemistry Homework Help
Replies
1
Views
684
Qualitatively assessing melting/boiling points.
    • Biology and Chemistry Homework Help
Replies
5
Views
5K
Chemistry Intermolecular Forces question
    • Biology and Chemistry Homework Help
Replies
9
Views
4K
Physical Properties Dimethyl ether vs ethanol
    • Biology and Chemistry Homework Help
Replies
1
Views
21K
Explanation for exception in a trend? - Chemistry
    • Biology and Chemistry Homework Help
Replies
1
Views
948
Are chemical messages between proteins intermolecular forces
    • Biology and Medical
Replies
3
Views
1K

Hot Threads

Recent Insights

Back
Top