The flashcards below were created by user
on FreezingBlue Flashcards.
What is an element?
A substance made of one type of atom
What is a compound?
A substance made of 2 or more elements chemically combined
Name the 3 sub-atomic particles.
How many protons, neutrons and electrons are in an atom of sodium?
(atomic number 11 and mass number 23)
- Protons 11
- Neutrons 23-11=12
- Electrons 11
Why do atoms have the same number of protons and electrons?
So the charges balance and the atom is neutrall overall
What is the charge on a proton, neutron and electron?
- proton +1
- neutron 0 (neutral)
- electron -1
What is the electron arrangement of these atoms?
a) carbon (6 electrons)
b) chlorine (17 electrons)
How are elements arranged in the periodic table?
in order of atomic number
Why do elements in the same group have similar chemical properties?
same number of outer electrons
Why are the elements in Group O unreactive?
they have a full outer shell of electrons
What is unusual about the elements in Group 1?
They are VERY reactive
Which gas is produced when sodium reacts with water?