Chemistry Test
Color change, precipitation, gas production, temperature change, change in characteristic properties
5 signs of a chemical change
Oxygen
An example of an element with a valence of six (6) would be: Oxygen Neon Chlorine Nitrogen
The water, or the liquid
In the mixture below, which part is the solvent?
Carbon Tetrachloride
The correct name for the following compound is? CCl(sub 4)
solutions will dissociate, suspensions will not
The difference between a solution and a suspension is:
molecule
The smallest part in which a covalent compound can be divided and still remain the same compound would be a _________________.
synthesis
The type of equation that would describe the OPPOSITE reaction, to make water would be called what?
Single displacement
What does this show?
number of valence electrons
What is the same within each group in the periodic table?
8
What is the total number of atoms involved in the following chemical reaction? 2H(sub 2)O(sub 2) ---> 2H(sub 2)O + O(sub 2)
polyatomic ion
a charged set of atoms held together by ionic bonds that act as an ion in atomic bonds
nona
common prefix for nine
chemical bond
interactions that hold atoms together in compounds
concentration of solution
the amount of solute per volume of solvent, usually given as g/mL of solution or in MOLES per liter
compound
two or more elements chemically bonded together
supersaturated solution
when heated, solution will temporarily be able to hold more solute than when saturated
ionic bond
A bond that forms when electrons are transferred from one atom to another is called a ____________.
six
How many carbon atoms are in this glucose molecule? C(sub 6)H(sub 12)O(sub 6)
0.3 g/ mL
If 30g of NaCl are added to 100 mL of water, the resulting solution will have what concentration?
a precipitate
In an experiment a student combined two clear liquids and produced a white solid. What is this solid called?
valence electrons
In order to determine if two chemical elements will form a chemical bond, you should know what about them?
2 sandwiches, 2 cheese left over
In the following reaction of making sandwiches, how many sandwiches will result from four pieces each of bread, meat and cheese? bread: 2 + meat: 2 + cheese: 1 ---> sandwich: 1
production of gas
In this reaction, two clear liquids are put together. What sign indicates that a chemical change has taken place?
polarity
Molecules or groups of atoms that have a definite positive and negative charge on one or the other side
NO(sub 2)
The products in this chemical formula are: 2NO(g) + O(sub 2)(g) ---> 2NO(sub 2)(g)
The Law of Conservation of Mass
The scientific law that states that matter cannot be created or destroyed in ordinary reactions is known as:
2
The symbol for iron is Fe. The chemical symbol for oxygen is O. The formula for iron oxide, a type of rust, is Fe(sub 2)O(sub 3). How many iron atoms are in one molecule of iron oxide?
Add the coefficient 2 to BOTH H(sub 2) and H(sub 2)O
To balance the following equation, what should be done? H(sub 2) + O(sub 2) ---> H(sub 2)O
mixture
Two or more pure substances put together are known as a ________________.
The solution has precipitated.
What is happening to this tube?
coefficients
When balancing a chemical equation, the _________________ may be changed for each compound.
Ca + O(sub 2) ▬► CaO(sub 2)
Which of the following chemical equations is balanced? 3Ca + O(sub 2) ▬► 5CaO(sub 2) Ca + 2O(sub 2) ▬► 2CaO(sub 2) Ca + O(sub 2) ▬► CaO(sub 2) 3Ca + O(sub 2) ▬► 3CaO(sub 2)
change of state
Which of the following is NOT a sign of a chemical change? precipitation formation of a gas change of state temperature change
ice melting
Which of the following is a physical change? burning wood ice melting metal rusting food digesting
Sodium chloride
Which of the following is an ionic compound? Water Nitrogen Sodium Chloride Carbon Dioxide
The darkest liquid
Which of the following solutions of copper sulfate, a blue liquid, is likely to be saturated?
coefficient
a number placed in front of a molecule or formula unit to indicate the number of this compound in the reaction
chemical equation
a representation of a chemical reaction showing reactants and products
formula unit
a set of atoms held together by ionic bonds
precipitate
a solid that forms during a chemical change
product
a substance that is formed through the change in a chemical reaction
reactant
a substance that participates in the chemical reaction
covalent bonds
atoms share one or more pairs of electrons
chemical changes
changes which cannot be easily reversed
physical changes
changes which some can be reversed
ions
charged atoms formed by the exchange of electrons
octa
common prefix for eight
penta
common prefix for five
tetra
common prefix for four
mono
common prefix for one
hepta
common prefix for seven
hexa
common prefix for six
deca
common prefix for ten
tri
common prefix for three
di
common prefix for two
Ionic bonds
exchange of electrons, causing atoms to be attracted to each other
metallic bond
form between metals due to opposite charges
solution formation
ions dissociate in a solution becoming evenly distributed throughout the solvent
The Law of Conservation of Mass
matter cannot be created or destroyed in a chemical reaction
synthesis, decomposition, single displacement, double displacement
name four types of reactions
coefficients may be changed; subscripts may not
name two important steps in balancing equations
anions
negative ions (gain electrons)
heterogeneous mixture
not uniform throughout, usually will separate over time
suspensions
particle are temporarily distributed throughout the mixture, needs to be agitated to continue or will separate
cations
positive ions (lose electrons)
saturated solution
solution with the maximum amount of solute per volume of solution that the solvent can have under those conditions
chemical formula
symbols and numbers that represent a compound
solubility
the maximum amount of solute that can dissolve under normal conditions
valence electrons
the number of electrons in the OUTER shell available for bonding
molecule
the smallest unit of a covalently bonded atom or group of atoms
homogeneous mixtures
uniform throughout, stay in solution over time
