Atoms, Elements And Compounds Flashcards
What are atoms?
Atoms are made up of protons, neutrons and electrons. They have the same number of protons as electrons.
What are elements?
An element is a collection of the same type of atoms (they have the same number of protons).
What are compounds?
A combination of at least two elements that are chemically bonded together.
What are mixtures?
A mixture is a combination of at least two elements that can be separated physically.
Name some distinctive features in metals.
- solid at room temperature (except Mercury)
- shiny if polished
- electrical conductors
- thermal conductors
- malleable (bend without breaking if solid)
- can stretch into wires (ductile)
Why is it called the Periodic Table?
The properties of elements in a group are found to have repeating or periodic behaviour. Elements having the same properties appear in the same column (group).
Who was Mendeleev?
Mendeleev was the Russian chemist who put forward the structure of the table and was so confident of his structure that he was able to identify the properties of elements that were unknown then. He was subsequently proven to be right.
What does it mean to balance an equation?
You must have the same quantity of atoms of the same type on either side.
What is an oxide?
Any compound that ends in oxide (oxide, monoxide, dioxide, etc.) is formed when an element is reacted with oxygen (burns).
What is a column in the Periodic Table called?
A column is called a group.
What is a row in the Periodic Table called?
A row is called a period.
What are the three types of elements?
Metals
Non-metals
Metalloids
What is a metalloid?
A metalloid has some properties of metals and some properties of non-metals. They also separate the metals/non-metals in a staircase shape.
Name at least three metalloids?
- boron (B)
- silicon (Si)
- germanium (Ge)
- arsenic (As)
- antimony (Sb)
- tellurium (Te)
- polonium (Po)
- astatine (At)
What are Lanthanides and Actinides?
They are elements 58-71 and 90-103 on the Periodic Table. They are displayed beneath the table, as there is not enough room.
