Chem A Flashcards
(26 cards)
What are the 3 subatomic particles
Protons, neutrons, electrons
What is an isotope?
Atoms of the same element but with a different number of neutrons
What is a compound?
Two or more different elements chemically bonded together
Who discovered electrons orbiting the nucleus in shells
Neils Bohr
Who made the plum pudding model
J.J. Thomson
How would you separate a mixture of sand and water?
Filtration
How would you separate a mixture of water and oil
Distillation
How would you separate a mixture of salt water and mud
Filtration then crystallization
Who made the framework for the modern day periodic table
Dimitri Mendeleev
What is a molecule
Two or more elements bonded together
How many electrons does each shell hold respectively
2 electrons, 8 electrons, 8 electrons
What is the nucleus of an atom made up of
Protons and neutrons
What does the atomic number represent
The number of protons which is equal to the number of electrons
What does the mass number represent
The number of protons + neutrons
How would you find the amount of neutrons in an atom of an element
Mass number - atomic number
Why dont the protons in the nucleus repel eachother and separate from the nucleus
Because of the neutrons in between the protons holding them together
What are group 1 elements called
Alkali metals
What are group 7 elements called
Halogens
What are group 0 elements called
Noble gases
What is the rate of reaction in group 1 (alkali) metals
Increases as you go down the group, outer electron if further away, more shells (shielding) therefore weaker attraction of nucleus to outer electrons
What is the rate of reactivity pattern in group 7 (halogens) elements
Decreases down the group
What is the reactivity of group 0 (noble gases) elements
They are unreactive
What is relative atomic mass
The average mass of one atom of an element to 1/12 of the mass of an atom of carbon-12
What is relative isotopic mass
The average mass of all isotopes
