Chemistry Flashcards
How many Periods are there?
7
How are Periods and Groups arranged?
All elements in a Period are completely different, whereas elements in a Groups are arranged according to their properties.
What is a molecule?
2 or more atoms chemically bonded together.
What is an element made from?
It’s made of atoms or molecules.
What is a compound made of?
Molecules
What is the formula for Nitrogen and Chlorine?
N with a little 2
CL with a little 2
What does the Nucleus of an atom contain?
Protons and neutrons
What is the Nucleus of an atom?
It is the middle?
What type of charge does the Nucleus of an atom have?
It has a positive charge because of the protons.
What is around the Nucleus of an atom?
Shells along with electrons
What type of charge does an atom have?
Atoms have a 0 overall charge . They are neutral.
What type of charge does a Proton have?
+1 (positive)
What type of charge does a Neutron have?
0 (neutral)
What type of charge does an Electron have?
-1 (negative)
What is the relative mass of a proton?
1
What is the relative mass of a neutron?
1
What is the relative mass of an electron?
1/2000
How big is an atom?
Atoms are tiny. They are not visible from the human eye but they make up everything. Atoms are mostly empty space!
What does conservation of mass mean?
matter can’t be destroyed or created
What is a mixture?
2 or more substances that are NOT chemically joined together.
How do you work out the number of neutrons in an element?
Mass number - Atomic Number