Chemistry of Life quizzes 1 and 2
Water can only dissolve inorganic compounds.
False
Salts help to maintain the natural ionic concentration of an organism.
True
Produces OH- ions
base
Select four of the most abundant elements found in plants and animals.
carbon oxygen nitrogen and hydrogen
A positively charged ion is called a(n) .
cation
HCl is an example of a(n)
compound, molecule
A water molecule is held together by a ______ bond.
covalent
A chemical bond formed between two atoms by the sharing of electrons.
covalent bond
A molecule of one atom of carbon and two atoms of oxygen would be written:
COv2
An organic molecule will always contain:
Carbon
Atoms which possess completed outer energy level or have a stable octet are inert.
true
Each element consists of only one type of atom.
true
Which valences have the greatest tendency to form ions?
+1 -1 +2 -2 +3 -3
The pH ranges between
0 and 14
If an atom is supplied with excess energy:
1.an electron may change to an excited state 2.an electron may move to a higher energy level
The pH of water is ______ because it contains an equal amount of H+ and OH- ions.
7
There are _______ elements that can be found to occur in nature.
92
Check the correct statements regarding a compound and a molecule:
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
All the subatomic particles participate in chemical reactions.
False
How is a sodium ion symbol written?
Na+
A substance which yields an anion plus a hydrogen ion is a(n):
acid
Any substance which donates a hydrogen atom during disassociation.
acid
produces H+ ions
acid
Select the characteristics of a hydrogen bond:
an attraction between polar molecules intermolecular force between hydrogen and oxygen, fluorine, or nitrogen
A negatively charged ion is called a(n) .
anion
A negatively charged ion; an atom which has gained an electron.
anion
Containing two atoms.
diatomic
Organic fats ________ dissolve in water.
do not
A subatomic particle, fundamental to all matter, existing in orbit around the nucleus of an atom and carries a negative charge.
electron
The common subatomic particles that make up an atom consist of protons, neutrons, and
electrons
The subatomic particles/ units which govern potential chemical reactions among elements are: .
electrons
Which statement is correct?
electrons of a neutral atom always equals the number of protons
An electron in the second energy level has more ______ than an electron in the first energy level.
energy
A hydrogen bond is completed by the transfer of its sole electron to another element.
false
Water molecules are attracted to each other by ______ bonds
hydrogen
An intermolecular force (attraction) occurring between a hydrogen atom and fluorine, oxygen, and nitrogen atoms.
hydrogen bond
A chemical compound not containing carbon.
inorganic
An electrically charged atom or group of atoms formed by the loss or gain of electrons.
ion
Inorganic compounds are usually held together by _____ bonds.
ionic
A bond formed by the electrical attraction between two oppositely charged ions.
ionic bond
An ionic bond:
is the attraction of two oppositely charged ions involves actual transfer of electrons
Anything which occupies space and has mass.
matter
What has mass and occupies space?
matter
Naturally occurring compounds in the earth are called
minerals
Two or more substances mixed together but not chemically combined.
mixture
A unit of matter representing the chemical properties of a substance composed of two or more atoms held together by chemical bonds.
molecule
The smallest unit of a compound is a(n)
molecule
A subatomic particle, fundamental to all matter except hydrogen, existing in the nucleus, with about the same mass as a proton, but carries no charge.
neutron
Atomic mass is determined by the number of protons plus
neutrons
The positively charged center of an atom which contains both the protons and neutrons of the atom.
nucleus
Any particular element can always be identified by its:
number of protons
Any chemical compound which contains carbon.
organic
A measure of the hydrogen ion concentration in a solution.
pH
A subatomic particle, fundamental to all matter, existing in the nucleus, with a positive charge and about equal mass to a neutron.
proton
Each unique element is determined by the number of _________ occurring in the atom.
protons
The word "synthesize" means:
put together
The compound formed by the ionic bonding of a cation and anion.
salt
When salts are dissolved in water they:
separate into ions
A substance which is dissolved in a liquid.
solute
A liquid which acts to dissolve or suspend solutes
solvent
A covalent bond is:
the sharing of electrons by two or more atoms
In nature, on Earth, matter can exist in________ phases.
three
Chemical reactions are the result of an atom attempting:
to rearrange its configuration to result in a complete outer energy level
The smallest unit of an element that still retains the chemical properties of the element.
atom
The smallest unit which retains the properties of an element is a(n)
atom
The mass of an element; approximately equal to the number of protons and neutrons in its nucleus.
atomic mass
The number of protons in the nucleus of the atom (Note: the number also equals the number of electrons around the nucleus).
atomic number
(or alkali)Any substance capable of combining with hydrogen; it normally donates a hydroxyl (OH-).
base
A substance which yields a cation plus the hydroxyl ion in water is a(n):
base
A positively charged ion; an atom which has lost an electron.
cation
The union between atoms by the interaction of their electrons in the outermost orbit.
chemical bond
When the atoms of elements or compounds interact to form at least one new compound.
chemical reaction
Valence is the number of electrons an atom must gain or lose in order to ______ its outer energy level or have a stable octet.
complete
A chemical substance composed of atoms of two or more distinct elements chemically bonded to one another.
compound
Many elements exist naturally as a diatomic molecule. This means that the element is found in nature as_____ chemically bonded atoms.
two
An ionic bond occurs when:
two atoms exchange electrons and become ions
The number of electrons an element must gain or lose in order to complete its outer electron shell.
valence
When will an atom give up electrons?
when less than half of the outer energy level is filled