Splitting the Atom Flashcards
What are atoms made of?
Protons, Neutrons and Electrons
What is inside the nucleus?
Protons and neutrons.
What is the mass number in the periodic table?
The sum of the protons and neutrons in the nucleus
What is the atomic number in the periodic table?
The number of electrons and protons in an atom.
Where are electrons found?
Orbiting the nucleus
What are the charges of the particles in an atom?
Protons are positive, neutrons are neutral and electrons are negative.
What charge is the nucleus?
Positive
What are the characteristics of a nucleus?
It is very small and dnese and contains protons and neutrons.
What are the regions containing electrons called?
Electron shells or clouds
How many electrons can the first shell hold?
2
How many electrons can the second shell hold?
8
How many shells can the third shell hold?
16
How do you calculate the number of neutrons of an atom?
Subtract the atomic number from the mass number.
Eg. Iron has a mass number of 56 and an atomic number of 26. 56-26=30 neutrons. Since each atom is neutral, the number of negative electrons=the number of positive protons=26 for Iron
How is the periodic table organised?
Horizontal rows called PERIOD and vertical rows called GROUPS
How many groups are there in the periodic table?
8 groups