Dispersion Forces

Dispersion Forces One of the three van der Waals forces is present in all condensed phases, regardless of the nature of the atoms or molecules composing the substance. This attractive force is called the London dispersion force in honor of German-born American physicist Fritz London who, in 1928, first explained it. This force is often referred to as simply the dispersion force. Because the electrons of an atom or molecule are in constant motion (or, alternatively, the electron’s location is subject to quantum-mechanical variability), at any moment in time, an atom or molecule can develop a temporary, instantaneous dipole if its electrons are distributed asymmetrically.

How to write a research paper fastThe presence of this dipole can, in turn, distort the electrons of a neighboring atom or molecule, producing an induced dipole. These two rapidly fluctuating, temporary dipoles thus result in a relatively weak electrostatic attraction between the species—a so-called dispersion force. Dispersion forces that develop between atoms in different molecules can attract the two molecules to each other. The forces are relatively weak, however, and become significant only when the molecules are very close. Larger and heavier atoms and molecules exhibit stronger dispersion forces than do smaller and lighter atoms and molecules.

Don't use plagiarized sources. Get Your Custom Essay on
Dispersion Forces
From $8/Page
Order Essay

F2 and Cl2 are gases at room temperature (reflecting weaker attractive forces); Br2 is a liquid, and I2 is a solid (reflecting stronger attractive forces). Trends in observed melting and boiling points for the halogens clearly demonstrate this effect, as seen in Table 1. Table 1. Melting and Boiling Points of the Halogens Halogen    Molar Mass    Atomic Radius    Melting Point    Boiling Point fluorine, F2    38 g/mol    72 pm    53 K    85 K chlorine, Cl2    71 g/mol    99 pm    172 K    238 K bromine, Br2    160 g/mol    114 pm    266 K    332 K  iodine, I2    254 g/mol    133 pm    387 K    457 K astatine, At2    420 g/mol    150 pm    575 K    610 K The increase in melting and boiling points with increasing atomic/molecular size may be rationalized by considering how the strength of dispersion forces is affected by the electronic structure of the atoms or molecules in the substance.

In a larger atom, the valence electrons are, on average, farther from the nuclei than in a smaller atom. Thus, they are less tightly held and can more easily form the temporary dipoles that produce the attraction. The measure of how easy or difficult it is for another electrostatic charge (for example, a nearby ion or polar molecule) to distort a molecule’s charge distribution (its electron cloud) is known as polarizability. A molecule that has a charge cloud that is easily distorted is said to be very polarizable and will have large dispersion forces; one with a charge cloud that is difficult to distort is not very polarizable and will have small dispersion forces.

Top Writers 4Me – FLAT 30% OFF: USE COUPON CODE 24/7HELP
Order NOW For A 30% Discount!
Pages (550 words)
Approximate price: -

Why Choose Us

Quality Papers

Top Writers4me provides the best top-grade academic writing services in compliance with our customers’ instructions. Have your paper written by a certified professional online college homework help writer to produce only high-quality essays with zero plagiarism.

Professional Academic Writers

You can now choose from a pool of online college homework help writers. Choose your writer and have them write the best content for you.Top Writers4me has, over the years, secured a team of the most reliable, experienced, and qualified writers. You can, therefore, trust that your assignment is in good hands.

Affordable Prices

We know that students have very limited budgets. And for that, we always strive to provide only the best, most affordable online college homework help services to our customers. Our goal is to provide top-quality assignment help services to all customers at the lowest, most affordable prices.

On-Time delivery

At Topwriters4me.com, we pay strict attention to deadlines. We recommend you to check out clients’ reviews for assurance that we will complete your assignments within the set deadlines. You can, therefore, trust that your paper will be done within and before the set deadline. Until now, we have not missed a single deadline.

100% Originality

Our Topwriters4me.com homework helper experts write only 100% original and plagiarism-free content for all of our clients. We also have a Quality Assurance Department team that goes through all work submitted by our writers multiple times. You can, therefore, rest assured that any signs of plagiarized or unoriginal content will be rejected before it reaches your portal.

Customer Support 24/7

Topwriters4me.com expert writers are always available 24/7 for customers who need assistance with using our website. You don’t have to check your watch the next time you want to have your assignment written. Our customer support is always available round the clock and ready to listen to your queries. Feel free to contact us via the Chat window or support email: support@topwriters4me.com.

Try it now!

Calculate the price of your order

We'll send you the first draft for approval by at
Total price:
$0.00

How it works?

Follow these simple steps to get your paper done

Place your order

Fill in the order form and provide all details of your assignment.

Proceed with the payment

Choose the payment system that suits you most.

Receive the final file

Once your paper is ready, we will email it to you.

Our Services

For years now, Topwriters4me.com has stood as a leader in providing its customers with the best online college homework help service in the industry. And all you have to do is provide us with the details of your order. Leave everything else to us. We’ve always got you covered.

Essays

Essay Writing Services

Since we launched, Topwriters4me.com deserved the best online “college homework help status” thanks to our essay ordering, writing, and delivery process. We deliver nothing but excellence in our results. Our essay writing services include impeccable grammar, zero-plagiarism, proper structure, and conformance to guidelines.

Admissions

Admission and Business Papers

Our top-quality online college homework help services guarantee that you will be accepted into your desired university. You just need to fill out your admission and business papers, and our team of online homework help workers will handle the rest. We will help you achieve and secure the best positions in your admissions forms.

Editing

Editing and Proofreading

At Topwriters4me.com, we have a skilled writing and editing team that’s dedicated to creating, editing, and restructuring for all types of papers. Our online college homework help editing and proofreading team will check, paraphrase, and correct any grammar mistakes on your paper before submitting the final document to you.

Coursework

Technical Papers

At Topwriters4me.com, we pride ourselves in having writers in almost all fields, even the most technical ones. You never have to worry about your paper being too technical for our certified online college homework help writers to handle. Mycoursewriter's team of writers can handle even the most complex writers. We will match your paper to the most competent writer that we believe will handle your paper the best way possible.

Open chat
Chat with us Live Here
Get in Touch with Our Live Chat Agents via WhatsApp on +1(346) 416-0954. Get Unlimited Access to Answers on Any Queries With Your Paper.