Atomic Structure And Periodic Table Flashcards
What does the mass number represent ?
The number of protons + neutrons
What does the atomic number represent ?
The number of protons
What does the groups represent ?
The amount of electrons in the outer shell of the element
What do the periods represent ?
Amount of shells
What’s an element ?
Made up from only 1 type of atom
Whats an atom ?
Smallest part of a substance
Whats a compound?
Made up of 2 or more different elements chemically bonded together
How do you separate pebbles and sand ?
Filtration
How do we separate gold and iron ?
Magnets
What is an isotope ?
An isotope is an atom that contains the same number of protons but a different number of neutrons to a similar element
Why is an atom overall neutrally charged ?
An atom is overall neutrally charged because it has the same number of protons and electrons
To find the number of neutrons you…
Subtract the atomic number from the mass number
What did daltons model suggest ?
He suggested that atoms were the smallest possible particle and each element was made up of unique atoms
What did Thomason’s plum pudding model suggest ?
Suggests the whole sphere is positively charged
What are neutrons used for ?
They are used for keeping the atom stable, they prevent 2 positively charged protons from repelling from each other
Why did Mendeleev leave gaps in his periodic table?
He left gaps because he knew that there were still undiscovered elements that would fit the properties of the gaps
What did Mendeleev discover ?
He realized that the physical and chemical properties of elements were related to their atomic mass and then arranged them so that each group contains elements with similar properties
How many electrons does the first, second and third shell hold ?
2,8,8
What are the 3 subatomic particles called ?
-Protons
-Neutrons
-Electrons
Where are the subatomic particles found ?
Protons- in the nucleus
Neutrons- in the nucleus
Electrons- the shells ( around the nucleus )
