What are atoms
Definition Atoms are incredibly small particles that make up everything in the universe. As far as we know, there are 118 different elements; around 92 that occur naturally and another 26 that scientists have created in laboratories (although this number fluctuates as scientists discover and create new elements). Each element is comprised of atoms that are unique to that element; hydrogen atoms are different from gold atoms, which are different from neon atoms.
Every atom is made up of three subatomic particles:
- Electrons - the smallest part of an atom, these particles are too small to measure. They are the 'planets' in the Rutherford-Bohr model of the atom as they rotate around the nucleus in a cloud. Electrons are negatively charged.
- Protons - found in the nucleus of an atom, these particles are the positively charged components of the atom.
- Neutrons - also found in the nucleus, the neutrons have no charge. Both the neutrons and protons are almost 2,000 times larger than the electrons.
Each element is different based on the number of protons and electrons it contains. An atom of hydrogen contains only one proton and one electron, while an atom of carbon contains six of each, and an atom of silver contains 47 protons and 47 electrons.
So there you have it. With just three numbers, the atomic number, the mass number, and the net charge, you can uniquely identify every kind of atom in the universe.
All matter is made of atoms. An atom consists of a central nucleus made of protons and neutrons, surrounded by zero or more electrons.
In order to classify an atom, we need to know how many protons it has, how many neutrons, and how many electrons.
The number of protons an atom has determines which element it is. An oxygen atom will always have 8 protons. A carbon atom will always have 6 protons. An atom of gold will always have 79 protons. If you’ve ever seen the periodic table of elements, you probably know that the elements are arranged on that table in order of the number of protons they have. The number of protons an atom has is called its atomic number.
Atoms are incredibly small particles that make up everything in the universe. As far as we know, there are 118 different elements; around 92 that occur naturally and another 26 that scientists have created in laboratories (although this number fluctuates as scientists discover and create new elements). Each element is comprised of atoms that are unique to that element; hydrogen atoms are different from gold atoms, which are different from neon atoms.
Every atom is made up of three subatomic particles:
- Electrons - the smallest part of an atom, these particles are too small to measure. They are the 'planets' in the Rutherford-Bohr model of the atom as they rotate around the nucleus in a cloud. Electrons are negatively charged.
- Protons - found in the nucleus of an atom, these particles are the positively charged components of the atom.
- Neutrons - also found in the nucleus, the neutrons have no charge. Both the neutrons and protons are almost 2,000 times larger than the electrons.
Each element is different based on the number of protons and electrons it contains. An atom of hydrogen contains only one proton and one electron, while an atom of carbon contains six of each, and an atom of silver contains 47 protons and 47 electrons.
So there you have it. With just three numbers, the atomic number, the mass number, and the net charge, you can uniquely identify every kind of atom in the universe.
All matter is made of atoms. An atom consists of a central nucleus made of protons and neutrons, surrounded by zero or more electrons.
In order to classify an atom, we need to know how many protons it has, how many neutrons, and how many electrons.
The number of protons an atom has determines which element it is. An oxygen atom will always have 8 protons. A carbon atom will always have 6 protons. An atom of gold will always have 79 protons. If you’ve ever seen the periodic table of elements, you probably know that the elements are arranged on that table in order of the number of protons they have. The number of protons an atom has is called its atomic number.
