Chapter 3-Atoms and Molecules

________= given mass of compound /sum of mass numbers of the elements present in a compound.

Mole

An atom consists of a(n) ________ that is surrounded by one or more negatively charged electrons.

central nucleus

A(n) ________ is a particle of matter that uniquely defines a chemical element.

atom

________ can be used to find out how the atoms of an element will combine with the atom (s) of another element to form a chemical compound.

Valency

A negatively charged ion is called ________

anion

________ are created when atoms join in a ratio of small whole numbers.

Compounds

A(n) ________ is an association of charged atoms.

polyatomic ion

The ________ was the most astonishing idea Dalton's atomic theory provided.

atomic mass

During a chemical reaction, the sum of the _________ of the reactants and products remain unchanged.

Masses

Ionic compounds are formed by the combination between ________ an ______.

Metal and non- metals

Mole is a link between the __________ and __________.

Mass of atoms & number of atoms

Those ions which are formed from single atoms are called _________.

simple ions

In a pure chemical compound, elements are always present in a ________ proportion by mass.

definite

The SI unit of amount of a substance is __________.

mole

The valency of an ion is _________ to the charge on the ion.

equal

The abbreviation used for length names of elements are termed as their _______.

symbol