Overview of Chemistry Terms
Chemistry Formulas
The smallest component that makes up an element is called an atom. Atoms that are neutral or ionised make up every solid, liquid, gas, and form of plasma. Atoms are incredibly tiny, measuring typically 100 picometers across. Due to the quantum effects, they are so small that it is impossible to predict their behaviour with sufficient accuracy using Classical Physics, as would be the case, for example, if they were tennis balls. Thus, it is the smallest unit of an element.
Each atom is made up of a nucleus and one or more electrons that are linked to it. One or more protons and a significant number of neutrons make up the nucleus.
Atom
Proton
Proton was discovered by Ernest Rutherford and it is a subatomic particle which has an elementary unit positive charge. It is the fundamental constituent of the atomic nucleus.
Neutron
Neutrons are subatomic particles bearing no charge and it is a constituents of the atomic nucleus. Chadwick discovered the presence of these particles when a thin sheet of beryllium was bombarded with alpha particles.
Electron
An electron is a subatomic particle that bears an elementary unit negative charge. It is also known as the primary charge carrier.
Atomic Number and Mass Number
Atomic Number
Given below are some important points about atomic numbers.
The atomic number of an atom is determined by counting all the protons in its nucleus.
It is symbolised by the letter "Z."
A specific element's atoms all have the same atomic number since all of its protons are the same.
Atomic numbers vary among atoms belonging to various elements.
For instance, all carbon atoms have an atomic number of 6, whereas all oxygen atoms have an atomic nucleus with eight protons.
Mass Number
Given below are some important points about mass numbers.
The mass of an atom is determined by the sum of the protons and neutrons.
It is symbolised by the letter "A."
Since protons and neutrons coexist in the atom's nucleus, they are collectively referred to as nucleons.
For instance, a carbon atom contains 6 protons and 6 neutrons. Its mass number is 12.
All atoms of an element have the same amount of protons, although they can have different numbers of neutrons. As a result, various isotopes of the same element can have different mass values.
An electron weighs practically nothing. As a result, an atom's atomic mass and mass number are practically equal.
Isotopes and Isobars
Atoms having the same atomic number and distinct mass number are termed isotopes. For example, protium, deuterium, and tritium are isotopes of hydrogen.
Isotopes
Atoms bearing the same mass number and distinct atomic number are termed isobars.
Isobars
Pure Substances, Compounds and Mixtures
Pure Substance
The matter with invariant chemical composition and distinct properties is termed a pure substance. For example, glucose, gold and water. It is classified into two forms: elements and compounds.
Compound
When two or more two atoms of different elements are combined together by chemical bonds in a definite proportion, a chemical compound is formed. For example, NaCl and baking soda.
Mixture
When a material is made up of two or more different pure substances, which may be present in it in any ratio in the form of suspension, solution or colloid is known as a mixture. For example, tea and sugar solution.
Summary
In this article about basic Chemistry terms, we have discussed some important Chemistry terms including atoms, protons, neutrons, electrons, atomic number, mass number, pure substance, compound and mixture. The study of matter and the substances that make it up is the focus of the scientific subdiscipline of Chemistry. The characteristics of these substances and the reactions they go through to produce new substances are also covered.
Atoms, ions, and molecules, which in turn make up elements and compounds, are the main subjects of Chemistry. Through chemical bonding, these chemical species frequently communicate with one another. With this, we would bring this article about basic terms of Chemistry to closure and hope it was fun to learn.
FAQs on Basic Chemistry Terms
1. What is an atom and what are its fundamental components?
An atom is the smallest unit of an element that retains the properties of that element. It serves as the basic building block of all matter. The three fundamental subatomic particles that make up an atom are:
- Protons: Positively charged particles found inside the atom's nucleus.
- Neutrons: Neutral particles (no charge) also located in the nucleus.
- Electrons: Negatively charged particles that orbit the nucleus.
2. What is the main difference between an atom's atomic number and its mass number?
The key difference lies in what they measure. The atomic number (Z) represents the number of protons in an atom's nucleus. It is unique to each element and defines its identity. For example, any atom with 6 protons is a carbon atom. The mass number (A) is the total count of protons and neutrons in the nucleus, giving an approximation of the atom's total mass.
3. How do isotopes and isobars differ from each other?
Isotopes and isobars both describe relationships between different types of atoms, but they are opposites:
- Isotopes are atoms of the same element (same atomic number) but with different numbers of neutrons, resulting in a different mass number. For example, Carbon-12 and Carbon-14 are isotopes of carbon.
- Isobars are atoms of different elements (different atomic number) that happen to have the same mass number. For example, Argon-40 and Calcium-40 are isobars.
4. What are the essential differences between a compound and a mixture?
A compound and a mixture both contain multiple substances, but they differ in how those substances are combined. A compound is a pure substance formed when two or more different elements are chemically bonded together in a fixed ratio, like water (H₂O). A mixture consists of two or more substances that are physically combined without a chemical reaction and can be in any ratio, like salt dissolved in water.
5. Why isn't the mass of electrons included when calculating the mass number of an atom?
The mass of an electron is extremely small compared to that of a proton or a neutron. A proton or neutron is approximately 1,836 times more massive than an electron. Because their contribution to the total atomic mass is so insignificant, the mass of electrons is considered negligible and is omitted from the mass number (A) calculation for simplicity and practicality.
6. How can isotopes of the same element have different masses but identical chemical properties?
An element's chemical properties, such as how it reacts with other elements, are determined by its electron configuration, which is dictated by the number of protons in its nucleus (the atomic number). Since all isotopes of an element have the same number of protons and electrons, their chemical behaviour is virtually identical. The difference in neutrons only affects physical properties like mass and nuclear stability.
7. What are some real-world examples of an element, a compound, and a mixture?
We encounter these basic chemical forms every day. Here are common examples:
- Element: A piece of copper wire is made almost entirely of copper (Cu) atoms.
- Compound: Common table sugar, or sucrose (C₁₂H₂₂O₁₁), is a compound where carbon, hydrogen, and oxygen atoms are chemically bonded.
- Mixture: The air we breathe is a mixture of gases, primarily nitrogen (N₂) and oxygen (O₂), that are physically mixed but not chemically bonded.
8. What are the main branches of chemistry?
Chemistry is a vast field, typically divided into five main branches that help categorise different areas of study:
- Organic Chemistry: The study of carbon-containing compounds, which are the basis of life.
- Inorganic Chemistry: The study of all other compounds, including metals, minerals, and non-metals.
- Physical Chemistry: Focuses on the physical principles, like energy and quantum mechanics, that underlie chemical systems.
- Analytical Chemistry: The science of identifying and quantifying the chemical components of substances.
- Biochemistry: The study of chemical processes that occur within living organisms.
9. Why is chemistry often called the 'central science'?
Chemistry is referred to as the 'central science' because it provides a fundamental understanding of matter and its interactions, forming a crucial bridge between other scientific disciplines. It connects the fundamental laws of physics with the complex systems studied in biology, explains the composition of materials in geology, and is essential for developing new technologies in medicine and engineering.
10. Who is known as the father of modern chemistry and what was his key contribution?
Antoine Lavoisier is widely regarded as the father of modern chemistry. His most significant contribution was the Law of Conservation of Mass, which states that matter is neither created nor destroyed in a chemical reaction. He also established a systematic method for naming chemical compounds and demonstrated the role of oxygen in combustion, moving chemistry from a qualitative to a quantitative science.
