Atomic Interactions - Wavefunctions, Orthogonality, Orbitals, Hybridization, & Bonding

Nobel Prize-winning theoretical chemist Linus Pauling wrote a most famous book in 1939, entitling it, The Nature of the Chemical Bond and the Structure of Molecules and Crystals: An Introduction to Modern Structural Chemistry.

There have been few facets of chemistry of greater importance.

Hybridization

Here, we will discuss basic concepts that we hope will lead our readers to a better understanding of what goes on between atoms. We will consider the bonding between carbon atoms in particular.

Wavefunctions

Quantum mechanics is a mathematical discipline that defines the nature and behavior of tiny particle systems, such as atoms and molecules.

At the atomic and subatomic level, particles and waves share similar properties, each isolated system containing one or more particles is described by a mathematically descriptive equation called a wavefunction.
Operators

In mathematics, numbers can be “operated on” to produce certain results. For instance, 3 and 4 can be operated on by multiplying them with each other, to produce the result, 12. Wavefunctions can be operated on in various ways to produce mathematical results that correspond to physical properties. If two wavefunctions are multiplied together yielding the value zero, the wavefunctions are said to be orthogonal.

Orthogonality

An approximate definition for the word orthogonal is perpendicular – this applies to wavefunctions that are orthogonal – they do not interfere with each other. Thus atomic orbitals are orthogonal – they don’t interfere with each other. Continue reading..

Is Distilled Water Safe? Can We Drink Distilled Water?

Distillation is one method of water purification. Is distilled water safe to drink or as good for you as other types of water? The answer depends on a few different factors.

In order to understand whether distilled water is safe or desirable to drink, let's take a look at how distilled water is made:

What Is Distilled Water?

Distilled water is any water that has been purified using distillation. There are multiple types of distillation, but all of them depend on separating components of a mixture based on their different boiling points. In a nutshell, water is heated to its boiling point. Chemicals that boil off at a lower temperature are collected and discarded; substances that remain in a container after the water evaporates also are discarded. The water that is collected thus has a higher purity than the initial liquid.

Can You Drink Distilled Water?

Usually, the answer is yes, you can drink distilled water. If drinking water is purified using distillation, the resulting water is cleaner and more pure than before. The water is safe to drink. The disadvantage to drinking this water is that most of the natural minerals in the water are gone. If these minerals are desirable (e.g., calcium, magnesium, iron), the distilled water might be considered inferior to mineral water or spring water. On the other hand, if the initial water contained trace amounts of toxic organic compounds or heavy metals, you might want to drink distilled water rather than the source water.

Continue reading..

Which is the strongest reducing agent in Periodic Table?

Reducing agent is a substance that causes something to be reduced. In other words reducing agent is a chemical substance that donates electrons to atoms of other elements. All the alkali metals are strong reducing agents as they have strong tendency of losing electrons and the reducing power increases.

Lithium (Li) is the strongest reducing agent in the periodic table. The E^o value (reduction potential) depends on the three factors that is sublimation, ionization and hydration enthalpies. With the small size of its ion lithium has the lightest hydration enthalpy which accounts for its high negative E^o value and its reducing power.

Lithium is the lightest metal known. It is least fusible, least dense and least soft of all alkali metals. Though lithium has the highest ionization energy, yet lithium is strongest reducing agent among alkali metals, because of its largest heat of hydration which sufficiently exceeds the ionization energy. Lithium has the lowest value of standard reduction potential among all the alkali metals, and hence it is best reducing agent.

In general oxidizing agent acts by acquiring electrons; a reducing agent by giving up electrons. Hence elements with high EA values and high electronegativities are oxidizing agents and elements of low ionization energies are reducing agents. The reducing strength of elements becomes progressively lower across the periods and higher down the groups. Thus fluorine should be the strongest oxidizing agent and lithium is the strongest reducing agent of all the elements.

What is the Definition of Formula Mass?

Formula Mass Definition

The formula mass of a molecule is the sum of the atomic weights of the atoms in the empirical formula of the compound.

Also Known As: formula weight

Formula Mass Units: Formula weight is given in atomic mass units (amu).

Formula Mass Example and Calculation

The molecular formula for glucose is C₆H₁₂O₆, so the empirical formula is CH₂O.

The formula mass of glucose is (12)+2(1)+16 = 30 amu.

Relative Formula Mass Definition

A related term you should know is relative formula mass (relative formula weight). This simply means the calculation is performed using relative atomic weight values for the elements, which are based on the natural isotopic ratio of elements found in the Earth's atmosphere and crust. Because relative atomic weight is a unitless value, relative formula mass technically does not have any units. However, grams are often used. When the relative formula mass is given in grams, then it is for 1 mole of a substance.

The symbol for relative formula mass is Mr and it is calculated by adding together the Ar values of all the atoms in the formula of a compound.

Relative Formula Mass Example Calculations

Find the relative formula mass of carbon monoxide, CO.

The relative atomic mass of carbon is 12 and of oxygen is 16, so the relative formula mass is:

12 + 16 = 28

To find the relative formula mass of sodium oxide, Na₂O, you multiply the relative atomic mass of sodium times its subscript and add the value to the relative atomic mass of oxygen:

(23 x 2) + 16 = 62

One mole of sodium oxide has a relative formula mass of 62 grams.

Gram Formula Mass

Gram formula mass is the amount of a compound with the same mass in grams as the formula mass in amu. It is the sum of atomic masses of all atoms in a formula, regardless of whether or not the compound is molecular. Continue reading..

What Are Elements?

An element or chemical element is the simplest form of matter in that it cannot be further broken down using any chemical means. Yes, elements are made up of smaller particles, but you can't take an atom of an element and perform any chemical reaction that will break it apart or join its sub-units to make a bigger atom of that element.

What Makes It a Different Element?

So, you may be asking yourself what makes one material a different element from another? How can you tell if two chemicals are the same element? Sometimes examples of a pure element look very different from each other. For example, diamond and graphite (pencil lead) are both examples of the element carbon. You wouldn't know it based on appearance or properties. However, atoms of diamond and graphite each share the same number of protons. The number of protons, particles in an atom's nucleus, determines the element. Elements on the periodic table are arranged in order of increasing numbers of protons.

Examples of Elements

The element with one proton is hydrogen. Helium contains two protons and is the second element. Lithium has three protons and is the third element, and so on. Continue reading..

Tips to Pass Chemistry Exam

Passing a chemistry exam can seem like an overwhelming task, but you can do this! Here are the top 10 tips for passing a chemistry exam. Take them to heart and pass that exam!


1. Prepare before the test:

Study. Get a good night's sleep. Eat breakfast. If you're someone who drinks caffeinated drinks, today is not the day to skip it. Similarly, if you never drink caffeine, today is not the day to start. Get to the exam early enough that you have time to get organized and relax.

2. Write down what you know:
Don't risk drawing a blank when confronted with a calculation! If you memorized constants or equations, write them down even before you look at the test.

3. Read the instructions.

Read the instructions for the test! Find out whether points will be deducted for wrong answers and whether you have to answer all of the questions. Sometimes chemistry tests allow you to choose which questions to answer. For example, you may need to only work 5/10 problems. If you don't read the test instructions, you might do more work than you need to and waste valuable time. Continue reading..