Chemistry Flashcards
What does plum pudding model look like
A sphere of positive charge, with negative electrons embedded in it.
Element
substances made of one type of atom.
What did Dalton say the atom looked like? (daltons model)
The atom is a solid sphere, that cant be split into smaller pieces.
Compounds
different types of atoms checmically bonded together.
Mixture
consists of two or more elements or compounds that are not chemically combined together.
What does the nucleus of an atom contain?
protons and neutrons
How did scientists perform the alpha scattering experiment?
They fired alpha particles at a piece of thin gold foil.
What did scientists expect to see during the alpha scattering experiment? What did they actually see instead?
They expected the particles to travel straight through the gold. Instead, many were deflected
What did scientists learn about the atom, thanks to the alpha scattering experiment?
The atom has a small positive nucleus.
What is the relative charge of protons, neutrons and electrons?
Proton: +1
Neutron: 0
Electron: -1
What is the relative mass of protons, neutrons and electrons?
Protons: 1
Neutron: 1
Electron: 0 (very small)
What does the nuclear model look like?
Electrons orbit the nucleus.
What does the electron shell model / bohr model look like?
Electrons orbit at different energy levels (known as shells) around the nucleus.
What is relative atomic mass
The average mass of all the atoms of an element.
What is an isotope?
Atoms of the same element but with a different number of neutrons.
