MOLECULAR BASIS OF LIFE

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

three

A molecule of sulfuric acid contains two hydrogen atoms, one sulfur atom, and four oxygen atoms. Which of the following is the correct chemical formula for sulfuric acid? H2SO4 2H1S4O H2SO4

(A) H2SO4

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

(A)A compound consists of two or more distinct bonded atoms (C)a compound consists of any two or more atoms chemically bonded (D)a molecule is the smallest chemical subunit of a compound

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

(A)electrons of a neutral atom always equals the number of protons

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

(C) CO 2

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

(C)a molecule of two Nitrogen atoms

Complete the table of the following element. Element: Sodium

11 12 11 11 23

Match the following. 1. The smallest unit of an element 2. The area surrounding the nucleus of an atom in which electrons are normally located 3. The number of protons in the nucleus of the atom 4. Atoms of two or more elements chemically bonded to one another 5. The positively charged center of an atom 6. Exists in energy levels around the nucleus of an atom and carries a negative charge 7. Two or more atoms held together by chemical bonds 8. Anything which occupies space and has mass 9. Two or more substances mixed together but not chemically combined 10. The mass of an element 11. A subatomic particle that carries no charge 12. Containing two atoms 13. A subatomic particle with a positive charge ____diatomic ____electron ____neutron ____molecule ____nucleus ____mixture ____atomic number ____atomic mass ____energy level ____compound ____proton ____matter ____atom

12. diatomic 6. electron 11. neutron 7. molecule 5. nucleus 9. mixture 3. atomic number 10. atomic mass 2. energy level 4. compound 13. proton 8. matter 1. atom

Complete the table of the following element. Element: Chlorine

17 18 17 17 35

Choose the total number of each item requested below. 4C6H12O6 Carbon atoms: ________ Hydrogen atoms: ________ Oxygen atoms: ________ Molecules: ________

24 48 24 4

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

92

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

True

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

atom

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

compound molecule

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

What has mass and occupies space? volume matter energy density

matter

Naturally occurring compounds in the earth are called _____________.

minerals

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

molecule

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

neutrons

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

nitrogen hydrogen carbon oxygen

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

number of protons

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