Chem exam 2

law of conservation of mass

States that mass is neither created nor destroyed in a chemical reaction; it remains constant

law of multiple proportions

If two elements can combine to form more than one compound, the mass of one element that combines with a fixed mass of the other element, are in the ratio of small whole numbers

law of constant composition

in any particular chemical compound, samples of that compound will be made up of the same elements in the same proportion or ratio

average atomic mass

which of these materials are usually poor conductors of heat and electricity?

nonmetals

who was the scientist who determined the magnitude of the electric charge of the electron

Robert Millikan

When J. J. Thomson discovered the electron, what physical property of the electron did he measure?

its charge-to-mass ratio, e/m

Which of these scientists developed the nuclear model of the atom?

Ernest Rutherford

Rutherford's experiment with alpha particle scattering by gold foil established that

protons are not evenly distributed throughout an atom.

Atoms of the same element with different mass numbers are called

isotopes

Two isotopes of an element differ only in their

atomic mass

Which of these elements is chemically similar to magnesium?

calcium

Which of these elements is chemically similar to potassium?

Cesium

What are the three types of radiation produced by the decay of substances like uranium?

alpha, beta, and gamma radiation

where are the alkali metals located?

group 1A

where are the alkaline earth metals located?

group 2A

where are the halogen elements located?

Group 7A

where are the noble gases located?

Group 8A