What is the difference between atom molecules and compound?
A compound is a substance that is composed from two or more different elements. Water (H2O), table salt (NaCl), carbon dioxide (CO2), methane (CH4) and chlorophyll (C55H72O5N4Mg) are a few examples of compounds. Nitrogen gas (N2) is a molecule because the bond between the nitrogen atoms is a molecular bond.
A molecule may consists of atoms of one element only or may be more than one. But a compound is formed when atoms of at least two different elements combine. For example N2 is a molecule but not a compound and H2O is a molecule as well as a compound. So all compounds are molecules, but all molecules are not compounds.
- A compound is a substance formed when two or more chemical elements are chemically bonded together. The type of bonds holding elements together in a compound can vary: two common types are covalent bonds and ionic bonds. The elements in any compound are always present in fixed ratios.
- Elements are pure substance consisting of only one kind of atom. A molecule can have different number of same type of atoms (ozone - 3 oxygen atoms whereas, oxygen - 2). Here I have mentioned that ozone contains oxygen atom. But ozone is a molecule (found in atmosphere) and oxygen is the element.
- air is not a mixture because of scientists freezing it and finding different liquids, it is a mixture because the compounds that make up air e.g. oxygen (o2), Carbon dioxide (co2) and the most important Nitrogen which is an element and makes up 78.09% of air are not chemically bound in the way that compounds are
The only difference between a molecule of a compound and a molecule of an element is that in a molecule of an element, all the atoms are the same. For example, in a molecule of water (a compound), there is one oxygen atom and two hydrogen atoms. But in a molecule of oxygen (an element), both of the atoms are oxygen.
- A molecule is formed when two or more atoms of an element chemically join together. If the types of atoms are different from each other, a compound is formed. Not all molecules are compounds, since some molecules, such as hydrogen gas or ozone, consist only of one element or type of atom.
- The only difference between a molecule of a compound and a molecule of an element is that in a molecule of an element, all the atoms are the same. For example, in a molecule of water (a compound), there is one oxygen atom and two hydrogen atoms. But in a molecule of oxygen (an element), both of the atoms are oxygen.
- An atom has a nucleus surrounded by electrons. But when three oxygen atoms combine to form an O3 molecule, it becomes Ozone. So another difference between atoms and molecules is that when similar atoms combine together in varying numbers, molecules of different properties can be formed.
Every combination of atoms is a molecule. A compound is a molecule made of atoms from different elements. All compounds are molecules, but not all molecules are compounds.
- A compound contains atoms of different elements chemically combined together in a fixed ratio. An element is a pure chemical substance made of same type of atom. Compounds contain different elements in a fixed ratio arranged in a defined manner through chemical bonds.
- Binary molecular compounds are composed of only two elements. Molecular compounds are more difficult to name because the atoms combine through covalent and not ionic bonds. Therefore we cannot use the electrical neutrality rule for these compounds. Most molecular compounds are made from nonmetals.
- All organisms need four types of organic molecules: nucleic acids, proteins, carbohydrates and lipids; life cannot exist if any of these molecules are missing.
- Nucleic Acids. The nucleic acids are DNA and RNA, or deoxyribonucleic acid and ribonucleic acid, respectively.
Updated: 21st October 2019