Ch. 4 Review PS19

molar mass is

Democritus's original atomic theory was revised because it

mole- SI unit that describes the

average atomic mass is a weighted average, so

Oyxgen-16, Oxygen-17, Oxygen-18 are examples of

Mass number

Isotopes contain the same number of protons but different number of

valance electrons determine an atom's

What is unique for any given element

dense positively charged mass concentrated in the center of an atom

Dalton's atomic theory stated that ,

atoms have no electric charge because they have equal number of

When an atom gains or loses energy, some of its _____ may move from one level to another energy levels

unit of light

Thomson made his discovery about the atom during what experiment

Dalton's atomic theory was accepted because

The region in which an electron is most likely to be found

Who's model of the atom represents electrons traveling around the nucleus in fixed energy levels with energies that vary

Protons and ____ have almost the same mass

To find the number of ______in an atom you subtract the atomic number from the mass number

Modern atomic theory - which is NOT true

Atomic Number

A atom in an ______ state has more energy and is less stable than the atom in the ground state

What is found in the nucleus of an atom

___ experiments provided evidence that an atom contains negatively charged particles

protons have a __ charge

In Rutherford's experiment, what caused some of the alpha particles to be deflected

The atomic number of an element is the number of

Thomson discovered a subatomic particle that had a _____ charge

When all of the electrons in an atom are in orbitals with the lowest possible energy the atom is in its ____ state

Which of the following is not an orbital

Greek philosopher ___ devised the word "atom ": a tiny piece of matter that cannot be divided

Avogadro's number is defined as the number of particles in

subatomic particle with a negative charge

according to the new atomic theory electrons behave like

Which of the following is not a part of Dalton's atomic theory

found on the energy level of an atom

If an electron moves to a higher energy level, it

according to the modern atomic theory, it is nearly impossible to determine an electron's exact

neutrons have ___ charge

What is the mass number of 30 protons and 30 neutrons

atomic mass of carbon is 12 u, 1 mole of carbon 12 will have a mass of

The charge of an atom is