How many significant digits are in the number 1.0050?
5
100
In a chemical reaction, what never changes? (pick all that apply)
a) total numbers of molecules
b) total numbers of each type of atom
c) total mass
d) types of molecules
e) types of atoms
b) total numbers of each type of atom
c) total mass
e) types of atoms
100
What state of matter is best described by its molecules being extremely far apart?
What is a gas.
100
Identify the solvent: Chocolate syrup is dissolved in milk.
What is milk.
100
What is the formula for Magnesium iodide?
What is MgI2
200
Report the number 0.00456 in scientific notation.
4.56 x 10^-3
200
Balance the following reaction:
Fe2O3 + CO → Fe + CO2
(1) Fe2O3 + (3) CO → (2) Fe + (3) CO2
200
What is the name of the strongest intermolecular force?
hydrogen bonding
200
What is a unique characteristic of colloids?
They scatter light or display the Tyndall effect.
200
In What type of reaction do two or more compounds react to form one product?
What is synthesis
300
How many kilograms is 5,678 grams?
5.678 kg
300
For the reaction: N2 + 3H2 → 2NH3
How many moles of hydrogen are required to produce 4 moles of NH3?
6 moles
300
What happens to the pressure of a gas when volume increases? (Increases, decreases, stays the same)
Decreases
300
Name one factor that increases the solubility of a sugar cube.
Increasing the amount of solvent
Increasing the temperature of the solvent
Increasing the surface area of the solvent
agitating/stirring a solution
300
What is the name of the ions that do not appear in a net ionic equation?
What are spectator ions.
400
What is the unit of measurement for volume?
What is liters or milliliters.
400
For the reaction: N2 + 3H2 → 2NH3, how many grams of hydrogen are required to react with 1 mole of N2?
6 grams
400
Of the following liquids with their corresponding boiling points:
Water 100 C
Methanol 65 C
Ethanol 78.5 C
Which liquid has the weakest forces of attraction present?
Methanol
400
True or False (with correct explanantion): 14 kt gold is a solution.
True. Since solutions are homogeneous mixtures, gold is a mixture of several metals and 14kt gold only exists in one phase.
400
When naming an ionic compound, the second part of the name consists of
What is the anion or nonmetal.
500
A wood block has a density of 5 g/cm^3. The wood block is chopped in half. What is the density of the new wooden block?
5 g/cm^3. Density is a property that is characteristic for a particular type of substance. It never changes.
500
For the reaction: N2 + 3H2 → 2NH3, how many grams of hydrogen are required to react with 6 grams of nitrogen gas?
1.29 grams
500
Of the following gases, which would diffuse most rapidly through a small opening? (Must explain why.)
O2, Ar, N2, H2, Cl2
H2 (because it has the smallest molar mass, and moves the fastest)
500
True or false: Solubility of gases increase with temperature. (Must give correct explanation)
False: At high temperatures, gases have high kinetic energy and are more likely to evaporate than stay in solution.
500
What is the precipitate in the reaction between barium chloride and sodium sulfate?