AP Chemistry Semester 1 Exam Review
What volume of 0.5 M H2SO4 will be required to exactly neutralize 250 ml of 1 m NaOH?
250ml
Ammonia gas is produced by the reaction of hydrogen gas with nitrogen gas. IF 28 g of nitrogen gas is reacted with 28 g of hydrogen gas, what mass of ammonia is produced?
34.0 g
Four phosphorus atoms are contained in one molecule of phosphorus. One mole of phosphorus molecules will contain
4 moles of phosphorus atoms.
How many significant figures are contained in the measurement 0.0004510 g?
4 sig fig
Which isotope is represented in the drawing shown below?
47Sm 62
The empirical formula for a newly synthesized organic compound is C3H5O2N. The molar mass of this compound is 261 g. What is the molecular formula of this compound.
C3H15O6N3
The following two drawings show a sample of a gas at two different times. What difference in conditions could cause the change shown in the second drawing?
The atmospheric pressure becomes greater.
A chemist wants to determine the energies of electrons within an atom. Which of the following analyses would give her the information she is seeking?
Emission or bright line spectra
Which of the following elements will react with KCl (aq)?
F2
Which of the following ion pairs will most likely form a precipitate when combined in aqueous solution?
Fe3+ and S2-
Identify the chemical property from the following list.
Flammable
When Ernest Rutherford fired alpha particles at a thin sheet of gold foil. most of the particles passed through the foil with little or no reflection. The best interpretation ofthis data is:
Gold atoms are made of mostly empty space.
Which correctly shows the the order in which each gas will reach the other end of the tube?
H2>O2>CO2>Ar
Which of the following statements is true?
Helium and argon are chemically similar because they both have full valence levels.
Which of the following elements is likely to have the greatest difference in between the first and second ionization energies.
Rubidium
A particle contains 14 protons, 15 neutrons, and 12 electrons. Which of the following correctly identifies this particle?
Si4+
The temperature of a solution is measured as -34 degrees celcius. What is the temperature in degrees kelvin.
+239 K
The formal charge of the hydrogen atoms in the diagram below is, while the formal charge on the carbon is?
0,0
you can convert milligrams into grams by multiplying the number of milligrams by...
0.001
The molecular view in the diagram below represents an aqueous solution of ammonia. If each molecule shown represents 0.010 mol of molecules, what is the concentration of the solution?
0.02M
In the following reaction the iodine ion in HI is oxidized by the permanganate ion. A 5.0 mL solution of 0.20 M HI requires 4.0 ML of KMnO4 to completely oxidize all the iodide. What is the molarity of the KMnO4 solution?
0.05 M
The concentration of Ca+2 in impure tap water can be determined by the addition of Na2CO3 to a water sample to produce insoluble CaCO3. Excess sodium carbonate solution is added to a 1.0 L sample of tap water and the precipitate that formed was filtered, dried, and had a mass of 0.1001 g. What was the concentration of calcium in the original water sample?
1.0 x 10^-3 M
The density of gold is 19.3 g/cm. What volume of gold must be used to produce a peice of the metal that has a mass of 1.93 kg.
1.00 x 10^2
What is the answer to (2.04 x 10^3)(5.00 x 10^-6) in scientific notation
1.02x10^-2
Ethane gas undergoes combustion as shown by the equation below. What volume of water is vapor by the complete combustion of 4.05 L of ethane gas?
12.2L
The formula mass for barium hydroxide is 171.3 amu. What is the molar mass for this compound?
171.3 g/mol
An element has two stable isotopes. The first has a mass 202.9732 amu and a relative abundance of 29.52%. The second has a mass of 204.9744 amu and a relative abundance of 70.48%. Which number is the average atomic mass closest to?
204
What is the percent by mass of calcium in Ca(OH)2?
54%
How many neutrons are in the nucleus of an atom that has a Z number of 7 and a A number of 15?
8
An unknown white solid is gently heated. IT is observed that the color of the solid turns from white to black. What can best be concluded from this observation?
A chemical change must have occured because the color change indicates that a new substance has formed.
Which of these would be the most likely reason for the low reading?
A red solution absorbs light only of a complementary color.
The particle diagrams shown below represent a chemical reaction between elements A and B. Which best represents the balanced equation for the reaction?
A2 + B2 = 2AB
What is the correct formula for a compound that contains aluminum ions and oxide ions.
Al2O3
Which of the following oxides will most likely be amphoteric?
Al2O3
Which is the best description of the atom or ion illustrated above.
An anion of bromine with mass number 79 and a -1 charge.
Dry air is composed mainly of nitrogen gas and oxygen gas. Which of the following is a correct statement about humid air at the same pressure?
Humid air is less dense than dry air because lighter water molecules take the place of some of the molecules of nitrogen and oxygen.
Which of the following processes is true regarding the formation of a cation from a neutral atom?
It is more difficult to remove an electron from a cation than from a neutral atom.
which of the following elements are most likely to form an ionic bond with each other?
Magnesium and Iodine
Which of the following reactions involves the transfer of electrons from one species to another?
Mg+CuSO4=Cu+MgSO4
In the below reaction, what has an oxidation state of +4?
Mn in MnO2
Which of the following pairs of elements are most likely to have similar properties?
N and P
Many different compounds of nitrogen and oxygen exist. Which systematic name is correctly matched with its formula?
NOT SURE
THe mole ratio of carbon to hydrogen atoms (C:H) in a compound is 2.5:7.5. Which of these could be the molecular formula for this compound?
NOT SURE
The density of mercury is 13.6 g/cm. What is the mass of 2.00 liters of mercury.
NOT SURE
Which of these sets is arranged correctly in order of increasing size?
Ne<F-<O2-<N3-
This element is paramagnetic, has an ionization energy that is higher than that of carbon, has an atomic radius that is smaller than that of phosphorus and can form a stable anion with a -2 charge.
Oxygen
Which of the following molecules needs resonance structures to accurately describe its bonding?
PF5
The number of sig figs in a measurement is determined by the?
Precision of the measuring instrument.
The number of significant figures in a measurement is determined by the:
Precision of the measuring instrument.
An excess of silver nitrate solution is mixed with a solution containing an unknown concentration of calcium chloride. A precipitation reaction occurs and silver chloride is formed. The precipitate is filtered, dried and its mass is determined. This technique is used to determine?
The concentration of the chloride ions in the original solution.
Hydrogen chloride gas is converted into molecular chlorine and hydrogen gas in a cylinder fitted with a moveable piston. Assuming temperature and pressure are the same before and after the reaction, which of the following statements is correct?
The piston does not move, indicating no change in volume.
A sample of an unknown material was analyzed and was found to contain 28.1 g of silicon and 32.0 g of oxygen. What conclusion can best be made about this sample?
The sample must be SiO2, because the mole ratio is 1:2.
Two different samples, obtained in two different countries but appearing the same, were analyzed. The results of the analysis are shown in the table above. What can best be concluded from the data?
The samples are likely the same compound because the ratios of the elements are the same.
Sucrose is dissolved in pure water and its conductivity is tested. Which of the following is the best summary of and correct explanation for the results of this test?
The solution does not conduct electricity because water is a poor conductor and the sugar does not dissolve.
Which of the following gives you the most information about a molecule?
The structural formula
Element X is thought to be an alkali metal. What is the most likely formula for the compound that would result when ions of X combine with hydroxide ions?
XOH
