Biology A: Preparing for Quiz 1 Unit 2

In nature, on Earth, matter can exist in __________________ phases.

three

There are ____________ elements that can be found to occur in nature.

92

Exists in energy levels around the nucleus of an atom and carries a negative charge

electron

The subatomic particles/ units which govern potential chemical reactions among elements are: ___________________.

electron[s]

The common subatomic particles that make up an atom consist of protons, neutrons, and ___________________.

electrons

Which statement is correct? electrons of a neutral atom always equals the number of protons neutrons always equal the number of protons neutrons always equal the number of electrons atomic weight is identical to atomic mass

electrons of a neutral atom always equals the number of protons

Containing two atoms

diatomic

Check the correct statements regarding a compound and a molecule: a compound consists of any two or more atoms chemically bonded A compound consists of two or more distinct bonded atoms a molecule is the smallest chemical subunit of a compound a molecule may consist of two similar elements chemically bonded

A compound consists of two or more distinct bonded atoms a molecule is the smallest chemical subunit of a compound a molecule may consist of two similar elements chemically bonded

A molecule of one atom of carbon and two atoms of oxygen would be written: CO2 CO2 Co2 2CO

CO2

Each element consists of only one type of atom. True or False

True

Nitrogen gas consists of: two separate Nitrogen atoms a diatomic Nitrogen atom a molecule of two Nitrogen atoms A compound of Nitrogen atoms

a molecule of two Nitrogen atoms

The smallest unit of an element

atom

The smallest unit which retains the properties of an element is a(n) _____________________.

atom

The mass of an element

atomic mass

The number of protons in the nucleus of the atom

atomic number

Select four of the most abundant elements found in plants and animals. potassium argon carbon oxygen magnesium nitrogen sodium hydrogen

carbon oxygen nitrogen hydrogen

Atoms of two or more elements chemically bonded to one another

compound

HCl is an example of a(n): atom compound element mixture molecule

compound molecule

The area surrounding the nucleus of an atom in which electrons are normally located

energy level

Anything which occupies space and has mass

matter

What has mass and occupies space? energy matter volume density

matter

Naturally occurring compounds in the earth are called _____________________.

minerals

Two or more substances mixed together but not chemically combined

mixture

The smallest unit of a compound is a(n) _________________.

molecule

Two or more atoms held together by chemical bonds

molecule

A subatomic particle that carries no charge

neutron

Atomic mass is determined by the number of protons plus _________________.

neutrons

The positively charged center of an atom

nucleus

Any particular element can always be identified by its: number of electrons number of protons number of neutrons atomic mass

number of protons

A subatomic particle with a positive charge

proton

Each unique element is determined by the number of ___________________ occurring in the atom.

protons

Many elements exist naturally as a diatomic molecule. This means that the element is found in nature as ________________ chemically bonded atoms.

two