Protons, neutrons, electrons unit
If an atom has 12 positively charged subatomic particles, which of the following must it also have to be considered a neutral atom?
12 electrons
Which of Dalton's four postulates were proven to be incorrect
2 and 3
An atom has 10 protons, 15 neutrons and 10 electrons what is its mass number.
25
An element with a mass number of 11 and an atomic number of 5 has how many neutrons?
6
Neutron
A subatomic particle that has no charge and that is found in the nucleus of an atom, has mass
Dalton's 1st postulate
All matter is comprised of extremely small particles called atoms
Isotopes
Aroms of the same element that have the same number of protons but different number of neutrons
Neon-22, what is the 22?
Atomic mass
protons+neutrons=
Atomic mass
Dalton's 2nd postulate
Atoms cannot be subdivided, created, or destroyed
Dalton's 3rd postulate
Atoms of a given element are identical
Dalton's 4th postulate
Atoms of different elements combine in simple whole number ratios to form chemical compounds(Law of multiple proportion)
Nucleus
Center of an atom, very dense
Where are electrons found?
Electron cloud
Where is most of the volume in an atom found?
Electron cloud
What is an atom mostly made up of?
Empty space
Which scientist conducted experiments using alpha particles and thin gold foil, which later helped him develop his model for the atom?
Ernest rutherford
What determines isotope identity?
Number of neutrons
What determines an elements identity
Number of protons
How do you calculate the percent of something
Part/whole•100
The difference between nuclear atom model and the plum pudding model
Plum pudding model lacked a nucleus
The particles of the atom you can find by knowing the atomic number.
Protons and electrons
What subatomic particles would you find in the nucleus of an atom?
Protons and neutrons
Which subatomic particles contribute the most to the mass of an atom?
Protons and neutrons
Isotopes of the same element have the same number of ___________ and different numbers of _____________.
Protons,neutrons
Who determined the nucleus of an atom
Rutherford
When the number of protons is equal to the number of neutrons
The atom is neutral
Who determined the charge to mass ratio of an electron
Thompson
What was Thompson's conclusion following the cathode ray experiment?
electrons were deflected because they have the same charge as the negative plate
Electrons
negatively charged subatomic particles, no mass
Proton
positively charged subatomic particle, has mass
