The Atom
The fundamental building blocks of matter are atoms and molecules.
Atom- The smallest unit of an element that has the properties of that element.
Molecule- Neutral group of atoms held together by covalent bonds
Atomic Theory
Dalton's Atomic Theory was a foundation for modern chemistry, and it is the theory that we still use today. He conceived that:
Atomic Structure
Atoms are made of subatomic particles called protons, neutrons, and electrons.
Protons- Particles in an atom with a positive charge. Think "P" for Positive!
Neutrons- Particles in an atom with a neutral charge, they are neither positive or negative. Think "N" for Neutral!
Electrons- Particles in an atom with a negative charge.
The atom is made up of two different regions called the nucleus, and the electron cloud.
The fundamental building blocks of matter are atoms and molecules.
Atom- The smallest unit of an element that has the properties of that element.
Molecule- Neutral group of atoms held together by covalent bonds
Atomic Theory
Dalton's Atomic Theory was a foundation for modern chemistry, and it is the theory that we still use today. He conceived that:
- All matter is composed of atoms
- Atoms that are from the same element are the exactly alike
- Atoms that are from different elements are different
- Compounds are formed when atoms of two or more elements join together
- Atoms cant be created, destroyed, divided, or rearranged
Atomic Structure
Atoms are made of subatomic particles called protons, neutrons, and electrons.
Protons- Particles in an atom with a positive charge. Think "P" for Positive!
Neutrons- Particles in an atom with a neutral charge, they are neither positive or negative. Think "N" for Neutral!
Electrons- Particles in an atom with a negative charge.
The atom is made up of two different regions called the nucleus, and the electron cloud.
Nucleus
Contains all protons and neutrons Has a positive charge Contains almost all of the mass |
Electron Cloud
Contains all electrons Contains almost all of the volume |
Sometimes atoms are isotopes. That means they are atoms of the same element, but with different mass numbers.
Counting Atoms
In order to count the atoms in a chemical formula, you first have to be able to identify the individual elements in the formula.
If you are given the formula Fe2S3
Start on the left side of the formula and start to underline any capital latter followed by a lowercase letter until you reach the next capital letter.
Fe2S3
Fe2 is one element. Continue to do this to identify all of the other elements.
Fe2S3
S3 is the other element in this formula. After you identify all of the elements you can look at their subscripts to determine how many atoms they have.
Fe2 has a subscript of 2, so Fe has two atoms.
S3 has a subscript of 3, so S has 3 atoms.
If an element does not have a subscript, it is understood to have 1 atom.
Subscripts aren't available on weebly so just pretend the numbers to the right of each individual element is a subscript.
In order to count the atoms in a chemical formula, you first have to be able to identify the individual elements in the formula.
If you are given the formula Fe2S3
Start on the left side of the formula and start to underline any capital latter followed by a lowercase letter until you reach the next capital letter.
Fe2S3
Fe2 is one element. Continue to do this to identify all of the other elements.
Fe2S3
S3 is the other element in this formula. After you identify all of the elements you can look at their subscripts to determine how many atoms they have.
Fe2 has a subscript of 2, so Fe has two atoms.
S3 has a subscript of 3, so S has 3 atoms.
If an element does not have a subscript, it is understood to have 1 atom.
Subscripts aren't available on weebly so just pretend the numbers to the right of each individual element is a subscript.