Scientific Notation and Significant Figures
How many significant figures are in the number
0.0040500?
5
What substance composes all matter?
Atoms
Why do atoms have no electric charge?
What is a general formula for a chemical reaction?
Reactants yield Products
What is a mole in chemistry?
6.02 x 1023 atoms, molecules, particles
Determine the answer for the following calculation to the correct number of significant figures:
8.05 + 8.2 = ?
16.3
Salt water would be an example of what type of mixture?
Homogenous mixture
16O, 17O, and 18O are isotopes; they have the same number of _______, but a different number of _______.
protons; neutrons
When hydrogen and oxygen react to form water, what type of chemical reaction is this?
Combination/Synthesis
12.01 g of carbon = How many moles?
1 mol
Determine the answer for the following calculation to the correct number of significant figures:
5.0 x 5.0 = ?
25
Which of the tests measured physical properties?
a. reaction to flame and water
b. density, phase at room temperature
c. density, reaction to flame
d. phase at room temperature, reaction to water
b. density, phase at room temperature
What is the correct formula for Iron (II) Chloride
FeCl2
What type of chemical reaction is the reaction below?
8 Al(s) + 3 Fe3O4(s) → 4 Al2O3(s) + 9 Fe(s)
Single Replacement reaction
Maria reacted 90.00 grams of carbon disulfide with 50.00 grams of oxygen.
CS2 + 3 O2 --> CO2 + 2 SO2
If all of the carbon disulfide had reacted, 52.02 grams of carbon dioxide would have been produced. If all of the oxygen had reacted, 22.92 grams of carbon dioxide would have been produced. What was the limiting reactant and what was the theoretical yield?
Oxygen; 22.92 g CO2
Round the number 46,847,363,684 to TWO significant digits.
4.7 x 1010
Which of the following is an example of a chemical property of water? It:
a. Boils at 1000 C
b. Has no odor
c. Is transparent
d. Reacts readily with calcium
d. Reacts readily with calcium
When bonding magnesium (Mg) and nitrogen (N), how many of each atom do you need?
Mg = 3
N = 2
What would be the products based on the reactants?
NaOH + HNO3 -->
NaNO3 + HOH
Maria reacted 90.00 grams of carbon disulfide with 50.00 grams of oxygen.
CS2 + 3 O2 --> CO2 + 2 SO2
If next time, Maria uses 45.00 grams of oxygen, what will be the new theoretical yield of carbon dioxide?
20.6 g CO2
6.0 x 1024 / 2.0 x 1022
3.0 x 102
Phase changes involve the weakening or breaking of intermolecular forces. During phase changes molecules are not vibrating any faster.
A sample of element X contains 90% of X-35 atoms, 8.0% of X-37 atoms, and 2% of X-38 atoms. The average atomic mass will be closest to which value?
35.22 g mol-1
Balance the following equation and then determine the sum of the coefficients of the products:
__Pb(NO3)2 → __PbO + _NO2 + _O2
7
___Al(s) + __CuF2(aq) → __AlF3(aq)+ ____Cu(s)
If there are 4.87 moles of Cu produced, how many grams of Al reacted?
87.3 g Al