Chemistry Final Review
What is the pH of a substance that has a hydrogen ion concentration of 1.2 x 10 -2 M?
1.92
Which of following diagrams correctly represents the formation of a compound consisting of magnesium and fluorine?
1MG 7F
Chemists can identify the composition of some unknown salts by conducting a flame test. When potassium salts are heated in a flame, purple color is observed. This due to the movement of electrons between energy levels. What is the electron configuration of a potassium atom at ground state?
1s2 2s2 2p6 3s2 3p6 4s1
What is the percentage by mass of sodium (Na) in a formula unit of sodium hydrogen carbonate (NaHCO3)?
27.4%
How many molecules are in 0.500 mole of N2O5?
3.01 x 1o 23 molecules
Which of the following shows a correct Lewis dot structure?
5N
Use the equation below to answer the following question. BaCl2(aq) + Na2SO4(aq) ---> 2NaCl(aq) + BaSO4(s) The theoretical yield of BaSO4 is 58.35 g. If 44.34 g of BaSO4 are produced from the reaction shown above, what is the percent yield of BaSO4?
75.99%
The diagram below shows gas with an initial pressure of 3060 mm Hg in a cylinder at a constant temperature. The gas expands inside the Cylinder and pushes the piston up. What is the final pressure of the gas after the expansion?
784 mm Hg
Which of these is the electron-dot diagram for BR2(l)?
7Br7Br
A battery giving off a current producing bubbles in two test tubes. Which of the following best shows that the investigation results in a chemical change?
A burning wood splint placed above the mouth of the test tube on the right glows brighter when some gas is released from the test tube.
-Soft silvery-white color -Good conductor of thermal energy -Good conductor of electricity -Atoms contain a single valence electron These elements most likely belong to which group?
Alkali metals
A sample of a compound is added to distilled water in a clean beaker. A reaction occurs, and the water temperature drops rapidly. Which of the following statements is best supported by this observation?
An endothermic reaction occured
Which of these is an intensive property of this sample?
Boiling point
The diagram shows what happens when zinc reacts with hydrochloric acid. Which of these best describes the energy transformation that occurs during this reaction?
Chemical energy to Thermal energy
Sodium, mercury, argon, and neon are used in the production of lamps. There are fewer safety guidelines regarding the handling of neon and argon than for mercury and sodium. Which of the following best describes the elements within the group of periodic table that contains neon and argon gas?
Gaseous at room temperature and mostly unreactive with metals
What is the formula of the ion hydrogen sulfite, which has a charge of -1?
HSO3 -1
Which of following best explains why doubling the temperature of an ideal gas in a closed vessel doubles the pressure?
Increasing the temperature causes gas molecules to move more rapidly, striking the vessel walls more frequently and with greater force.
The solubility of an unknown substance was tested during an experiment. Based on the solubility curve information and the results of the experiment, what is most likely the identity of this unknown solute?
KNO3
Which of the following correctly matches a compound with its molecular geometry?
Methane (CH4): tetrahedral
Nuclear reaction. Which of the following best describes this reaction?
Nuclear fission is occurring because a nucleus is being split into smaller nuclei.
What is the chemical formula for disulfur decafluoride?
S2F10
Which of the following includes an example of a chemical property of an element?
Sodium is a solid at room temperature and reacts with other elements
X-ray crystallography is a technique that allows scientists to determine the ionic and atomic radii of elements. Which of these statements correctly describes a trend in ionic or atomic radii in the periodic table?
The atomic radius increases from top to bottom in a group.
Which of these statements is an accurate description of the ionization energies of elements in the periodic table?
The ionization energy of lithium is greater than that of potassium.
In a famous experiment conducted by Ernest Rutherford, positively charged charged alpha particles were scattered by a thin gold foil. Which of the following is a conclusion that resulted from this experiment?
The nucleus is very small and the atom is mostly empty space.
As a distant star moves away from Earth, the light given off by the star has a measurably lower frequency becomes lower?
The wavelength becomes longer, and the energy decreases.
The graph shows a solubility curve of ammonia gas and solubility measurements taken at different temperatures. Between which two points did the ammonia solution change from being unsaturated to saturated?
V to W
When zinc is exposed to air, zinc oxide is produced. What happens in this reaction?
Zinc is oxidized, and oxygen is reduced.
What is the electron configuration for an atom of germanium at ground state?
[Ar]4s23d104p2
The black substance is classified as-
a compound
Heart cells require a certain balance of sodium and potassium ions to function. The blood, which is approximately 83% water, carries two types of ions to the heart. The property of water that allows it to carry ions to the heart is its-
polarity
