April 13, 2017
Chemistry has taught us many things, and the basics of it has taught us about the things that matter consists of, with lots of terms to be understood, for example: Atoms, elements, substances, molecules, compounds, etc.
We all know that a substance is made up of elements and atoms, but do you really know what the difference is between the two?
Elements are the simplest form of substances, and are also considered to be pure substances that cannot be split or broken into simpler substances. However, they are still made up of smaller particles ‘“ which can be molecules, ions, or atoms. Practically, an element is made up of one kind of atom. If you have steel as an element, it means that it should only consist of steel atoms. So, in essence, an atom is the smallest amount of an element.
When atoms combine or bind together via a chemical means, they form molecules. When only like atoms combine, they form elements, so technically, elements can be composed of molecules.
An atom can be considered as the smallest amount of an element. It is the simplest unit of matter, and has a closely packed nucleus in its center. Surrounding the nucleus is a cloud of electrons, which are the negatively-charged particles of an atom. In the nucleus of the atom, a mix of electrically neutral neutrons and positively-charged protons converge. There is, however, an exception. ‘Hydrogen-1’ is a nuclide which is found to be stable, even without a neutron.
Electrons float around the nucleus, but are bound by a force, and when these atoms bind themselves with other atoms, a molecule is formed. Electrically neutral atoms contain equal numbers of electrons and protons. An atom with a charge – which is either negative (it has an extra electron) or positive (it has an extra proton) – is called an ion.
The term ‘element’ only came about at the time the periodic table of elements was introduced. It is actually a table of different kinds of atoms based on their characteristics, such as the number of sub-atomic particles, and atomic weight. However, the term element was used to point out a particular constituent in the periodic table.
An element is a substance that is made entirely from one type of atom. For example, the element hydrogen is made from atoms containing just one proton and one electron. If you had very, very good eyes and could look at the atoms in a sample of hydrogen, you would notice that most of the atoms have no neutrons, some of them have one neutron and a few of them have two neutrons. These different versions of hydrogen are called isotopes. All isotopes of a particular element have the same number of protons, but can have different numbers of neutrons. If you change the number of protons an atom has, you change the type of element it is. If you change the number of neutrons an atom has, you make an isotope of that element. All known elements are arranged on a chart called the Periodic Table of Elements.
A compound is a substance made from two or more different elements that have been chemically joined. Some examples of compounds are water (H2O), table salt (NaCl), table sugar (C12H22O11) and chalk (CaCO3).
A mixture is a substance made by combining two or more different materials in such a way that no chemical reaction occurs. A mixture can usually be separated back into its original components. Some examples of mixtures are a tossed salad, salt water and a mixed bag of M&M's candy.
Source : http://education.jlab.org/qa/atom_02.html
http://www.differencebetween.net
assalamualaikum eko let me ask you about your posting. you try to explain more specifically about the mix and examples?
ReplyDeletewaalaikumussalam ferdi , in this post the definition of mixture is a combination of two or more pure substances in which each pure substance retains its individual chemical properties. Mixtures can be composed of solids, liquids, or gases.
Deletefor the example :
● Sea water - a mixture of water and various salts.
● Crude oil - a mixture of organic compounds - mainly hydrocarbons.
● Gunpowder - a mixture of potassium nitrate, sulfur and carbon.
● Dry Air - a mixture of nitrogen, oxygen, argon, carbon dioxide, neon and tiny traces of other gases. (Air normally also contains water vapor as part of the mixture.)
etc , thanks for your question dude ^^
if the homogeneous solution was added again a solute what happens explain your arguments?
ReplyDeletehi nina thanks for your question , i think if homogen solution was added again a solute , that chemicals will be a solution again , i mean solution is a homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent.
Deletefor another condition which is colligative character/properties if solution was added again a solute will produce a solution boiling point higher than the boiling point of the solvent, the vapor pressure and a lower freezing point than the solvent.
hope that answer your question .
whatever the nature of constituent elements of the compound?
ReplyDeleteA physical property is a characteristic that can be observed or measured. There are many types of physical properties that can be used to tell compounds apart. Let's look at some of the more common physical properties of compounds. Color and odor are physical properties. These are both very easy to observe using your sense of sight and smell. For example, the salt we learned about, which is actually the compound sodium chloride, is white and odorless, whereas the chemical compound hydrogen sulfide, which has the formula H2S, is colorless and smells like rotten eggs.
DeleteMelting point and boiling point are other common physical properties. When substances melt, they change from a solid to a liquid. The melting point is the temperature at which a solid substance melts. For example, a frozen cube of H2O, which you refer to as an ice cube, has a melting point of 0 degrees Celsius. When that temperature is reached, an ice cube begins to melt into liquid water. If you continue to turn up the heat, that liquid water will reach its boiling point, which is the temperature at which a liquid changes to a gas.
In the case of water, the boiling point is reached at 100 degrees Celsius. At that temperature, water turns into water vapor, or steam, like you might see floating over a pot of water on your stove. Of course, not all substances melt or boil at the same point. This helps us identify mystery substances. For instance, if you have a liquid that you are not sure what it is, you can boil it and determine its boiling point. You can also note other physical properties, like its color and odor. This information, gives you clues to help identify the mystery substance.
okay now my quetion, why A homogeneous mixture also called a solution? do you agree with that? if not can you explain about that? and the last can you explain difference between pure substances and elements? if they are same? please give me a reason!
ReplyDeleteok thanks for your question , i will answer that one by one .
Deletefirst , why A homogeneous mixture also called a solution?
because . When the components of a mixture are uniformly intermingled, or when a mixture is homogeneous, it is called a solution. Aqueous solutions, those containing water, are the most common solutions.
second, with the statement i agree we called that solution , but that mixture must HOMOGENEOUS if not homogen we can't call it solution .
different between pure substances and elements ?
look, An element is basically a substance that is made up of the same kind of atoms. It can be called a pure substance too. But elements are not the only kind of pure substances.
All pure substances are NOT elements. A pure substance is one whose building blocks are heterogenous in nature. That is, the atoms or molecules that make it are of the same type. But unlike elements, the building blocks of pure substances are not restricted only to atoms. Certain compounds are called pure substances too.
Example for element: All the members on the periodic table:Hydrogen, Helium,iron , copper etc
Example for pure substances: certain oils, distilled water, pure liquids, oils, etc
hope that answer your question . pardon me if in my answer there are not perfectly answer your question ^^
Hi Eko,you have nice blog, i want ask you :Is it true that atoms can be seen by the eye, according to the article I read that atoms can not be seen by the eyes but with the tools?
ReplyDeletehello hei , thanks for visiting, its true that atoms can be seen by the eye ?
ReplyDeleteSetting aside the fact that it's physically impossible to resolve an atom (about 1 nanometer across) with visible light (about 400 nm across), it's physiologically impossible. Your eye can't resolve objects below about a tenth of a millimeter. Your ocular resolution is about 1/60 of a degree, and the muscles can only focus the lens to an accomodation of 10 cm or so. The difference is a factor of 100,000.
So there are many things much, much larger than an atom that you can't see. You can't even see ordinary cells, which are still two orders of magnitude larger than the wavelength of light and six orders of magnitude larger than an atom.
That means you can see them with a microscope, which can magnify more than your eye lens can, but not with the naked eye. Atoms can't be resolved even with a microscope, because light is far bigger than the atom itself.
So even if your retinas responded to a wavelength of light that could resolve an atom, you still couldn't bring it into focus and have it land as a distinct spot on the retina.
what we do to kknow that matter as copound or mixture ?
ReplyDeletehi al , thanks for the question , let me try to answer
Deletethe condition is we just look at the physic characteristic of things and we want to know this it a compound or mixture .
we can know compound from the constituent elements , because they are still distinguishable for the example like NACL ( Salt ) , this compound is combine from two contrituent which is natrium and chloride , this compound created by chemistry reaction ( it must ) .
but mixture hard to differentiate , cause Comparison of components that make up a mixture of indefinite and indiscriminate not like compound .
second way to know that things is compound or mixture is with the "separation process" , the compound only can separated with chemistry reaction but mixture can be separated without chemistry reaction , precisely with mechanical process where we can do itself in laboratory ^^ .