Flashcards CHEM 105: Atoms and Isotopes

What is matter?

Anything that takes up space and has mass

What is an atom?

The smallest identifiable unit of an element

What are the subatomic particles and their charges?

Protons (+), neutrons (0), and electrons (-)

_______ and _______ are found in the nucleus of an atom.

protons, neutrons

Protons and neutrons make up the majority of an atom's _____________ while most of the volume is from the ___________ ___________.

mass, electron cloud

What is an element?

A pure substance that cannot be broke down into simpler substances by chemical transformation

In the periodic table, the rows are referred to as ________ and the columns are referred to as __________ or ____________.

periods, groups, families

Every element has a unique number of __________, which is the same value as the atomic number.

protons

Isotopes have the same number of _________ but a different number of ___________.

protons, neutrons

Isotopes are all the same element, but have a different number of _________.

neutrons

In isotope symbol notation, the mass number goes on the _________ (top/bottom) while the atomic number goes on the __________ (top/bottom).

top, bottom

What is the formula to solve for neutrons in an isotope?

Mass number - atomic/proton number = # of neutrons

The number of electrons is (almost) always the same as the number of which subatomic particle?

protons

What is the difference between the average atomic mass and the mass number?

The mass number is always a whole number and is the sum of protons and neutrons, while the average atomic mass is usually a decimal and describes all atoms of the element mixed together

Column 1A refers to which group?

Alkali metals

Column 2A refers to which group?

Alkali Earth metals

Column 7A refers to which group?

Halogens

Column 8A refers to which group?

Noble gases

What is special about the noble gases?

They're inert. Their low reactivity means they are unlikely to form chemical bonds

Which columns make up the main group elements?

1A - 8A

The block in between the main group elements is which group?

Transition metals

Elements in the same _________ (group/period) have similar properties/reactivities.

group

Which three elements are metalloids and are underneath the staircase?

Ge, Sb and Po