Science Flashcards
What is an atom?
An atom is the smallest unit of matter that retains the properties of and element. It contains three subatomic particles; protons, neutrons and electrons.
What is a proton?
A proton is located in the nucleus of an atom and it is positively charged.
What is an electron?
An electron is located in the shells of atoms and they are negatively charged.
What is a neutron?
A neutron is also located in the nucleus and has a neutral charge.
What is an ion?
An ion is where the atom has either gained or loosed electrons in order for the outer shell to be full.
What is covalent bonding?
Covalent bonding is when two or more atoms share electrons and a molecule is formed. Eg: Sodium Chloride. A chemical bond formed by sharing electrons is called a covalent bond. Only non-metal atoms share electrons to form these.
What is polyatomic ions?
Polyatomic ions are ions that are made up of two or more atoms that are held together by covalent bonds.
What is the shell structure of an atom
The shell structure of atoms is this:
1st: 2 max
2nd: 8 max
3rd: 8 max
4th: 32 max
What does the atomic number represent?
The atomic number represents how many electrons and protons are in an element.
What is an Element symbol?
An element symbol is either 1 or 2 letters that make that element unique. No other element has the same.
What does the atomic mass represent?
The atomic mass represents the mass of the protons and neutrons added together. If you wanted to find out how many neutrons in an atom, you will subtract the atomic number from the atomic mass.
What are characteristics of non-metals?
The characteristics of non metals are:
1. Solid at room temperature, except for mercury, which is a liquid
2. Lustre
3. Good conductors of electricity and heat
4. Malleable
5. ductile
6. They usually melt at high temperatures.
What are characteristics of metals?
The characteristics of metals are:
1. brittle
2. They cannot be bent into shape
3. They are poor conductors of electricity and heat
4. They usually melt at low temperatures
What is a group in the periodic table and what does it represent?
A group in the periodic table are columns and they represent how many electrons are in the outer shell.
What is a period in the periodic table?
A period in a periodic table are rows and they refer to how many shells contain electrons.
What is an ionic compound?
An ionic compound is when cations and anions come together to make their outer shell full. The metals always lose their electrons and the non-metals always gain electrons.
What is the ion called if it loses electrons?
Cation
What is the ion called if it gains electrons?
Anions
