CHEMISTRY CST Practice

A weather balloon with a 2-meter diameter at ambient temperature holds 525 grams of helium. What type of electronic probe could be used to determine the pressure inside the balloon?
1. barometric
2. thermometric
3. calorimetric
4. spectrophotometric
Which would be most appropriate for collecting data during a neutralization reaction?
1. a pH probe
2. a statistics program
3. a thermometer
4. a graphing program
A scientist observed changes in the gas pressure of one mole of a gas in a sealed chamber with a fixed volume. To identify the source of the changes, the scientist should check for variations in the
1. air pressure outside the chamber.
2. molecular formula of the gas.
3. temperature of the chamber.
4. isotopes of the gas.
Electrical fires cannot be safely put out by dousing them with water. However, fire extinguishers that spray solid carbon dioxide on the fire work very effectively. This method works because carbon dioxide
1. displaces the oxygen.
2. renders the fire’s fuel non-flammable.
3. forms water vapor.
4. blows the fire out with strong wind currents.
In order to advance to the level of a theory, a hypothesis should be
1. obviously accepted by most people.
2. a fully functional experiment.
3. in alignment with past theories.
4. repeatedly confirmed by experimentation.
Matter is made of atoms that have positive centers of neutrons and protons surrounded by a cloud of negatively charged electrons. This statement is
1. a theory.
2. a hypothesis.
3. an inference.
4. an observation.
When a metal is heated in a flame, the flame has a distinctive color. This information was eventually extended to the study of stars because
1. the color spectra of stars indicate which elements are present.
2. a red shift in star color indicates stars are moving away.
3. star color indicates absolute distance.
4. it allows the observer to determine the size of stars.
Which of the following ordered pairs of elements shows an increase in atomic number but a decrease in average atomic mass?
1. Ag to Pd
2. Co to Ni
3. Ge to Sn
4. Cr to Mo
Why is cobalt (Co) placed before nickel (Ni) on the periodic table of the elements even though it has a higher average atomic mass than nickel?
1. Nickel has one more proton.
2. Cobalt was discovered first.
3. Nickel has fewer electrons.
4. Cobalt has a lower density.
Generally, how do atomic masses vary throughout the periodic table of the elements?
1. They increase from left to right and top to bottom.
2. They increase from left to right and bottom to top.
3. They increase from right to left and top to bottom.
4. They increase from right to left and bottom to top.
Iodine would have chemical properties most like
1. manganese (Mn).
2. tellurium (Te).
3. chlorine (Cl).
4. xenon (Xe).
The chart above shows the relationship between the first ionization energy and the increase in atomic number. The letter on the chart for the alkali family of elements is
1. W
2. X
3. Y
4. Z
Which of the following atoms has six valence electrons?
1. magnesium (Mg)
2. silicon (Si)
3. sulfur (S)
4. argon (Ar)
Which statement best describes the density of an atom’s nucleus?
1. The nucleus occupies most of the atom’s volume but contains little of its mass.
2. The nucleus occupies very little of the atom’s volume and contains little of its mass.
3. The nucleus occupies most of the atom’s volume and contains most of its mass.
4. The nucleus occupies very little of the atom’s volume but contains most of its mass.
What information do the experimental results above reveal about the nucleus of the gold atom?
1. The nucleus contains less than half the mass of the atom.
2. The nucleus is small and is the densest part of the atom.
3. The nucleus contains small positive and negative particles.
4. The nucleus is large and occupies most of the atom’s space.
Why are enormous amounts of energy required to separate a nucleus into its component protons and neutrons even though the protons in the nucleus repel each other?
1. The force of the protons repelling each other is small compared to the attraction of the neutrons to each other.
2. The electrostatic forces acting between other atoms lowers the force of repulsion of the protons.
3. The interactions between neutrons and electrons neutralize the repulsive forces between the protons.
4. The forces holding the nucleus together are much stronger than the repulsion between the protons.
Which equation correctly represents the alpha decay of polonium-214?
A 2-cm-thick piece of cardboard placed over a radiation source would be most effective in protecting against which type of radiation?
1. alpha
2. beta
3. gamma
4. x-ray
Which of the following is a monatomic gas at STP?
1. chlorine
2. fluorine
3. helium
4. nitrogen
When cations and anions join, they form what kind of chemical bond?
1. ionic
2. metallic
3. hydrogen
4. covalent
Some of the molecules found in the human body are NH₂CH₂COOH (glycine), C₆H₁₂O₆ (glucose),
and CH₃(CH₂)₁₆COOH (stearic acid). The bonds they form are
1. nuclear
2. metallic
3. ionic
4. covalent
What type of bond do all of the molecules in the table above have in common?
1. covalent
2. ionic
3. metallic
4. polar
The reason salt crystals, such as KCl, hold together so well is because the cations are strongly attracted to
1. neighboring cations.
2. the protons in the neighboring nucleus.
3. free electrons in the crystals.
4. neighboring anions.
Under the same conditions of pressure and temperature, a liquid differs from a gas because the molecules of the liquid
1. have no regular arrangement.
2. are in constant motion.
3. have stronger forces of attraction between them.
4. take the shape of the container they are in.
Which of the following elements has the same Lewis dot structure as silicon?
1. germanium (Ge)
2. aluminum (Al)
3. arsenic (As)
4. gallium (Ga)
Which substance is made up of many monomers joined together in long chains?
1. salt
2. protein
3. ethanol
4. propane
For the polymer, polyvinyl chloride,

(PVC), ~ CH₂CH(Cl)CH₂CH(Cl)CH₂CH(Cl) ~

the repeating subunit is
1. CH(Cl)
2. CH(Cl)CHCH₂.
3. CH₂CH.
4. CH₂CH(Cl).
Which element is capable of forming stable, extended chains of atoms through single, double, or triple bonds with itself?
1. carbon
2. oxygen
3. nitrogen
4. hydrogen
Proteins are large macromolecules composed of thousands of subunits. The structure of the protein depends on the sequence of
1. lipids.
2. monosaccharides.
3. amino acids.
4. nucleosides.
When someone standing at one end of a large room opens a bottle of vinegar, it may take several minutes for a person at the other end to smell it. Gas molecules at room temperature move at very high velocities, so what is responsible for the delay in detection of the vinegar?
1. the increase in the airspace occupied by vinegar molecules
2. the chemical reaction with nerves, which is slower than other sensory processes
3. attractive forces between the air and vinegar molecules
4. random collisions between the air and vinegar molecules
Methane (CH₄) gas diffuses through air because the molecules are
1. moving randomly.
2. dissolving quickly.
3. traveling slowly.
4. expanding steadily
The volume of 400 mL of chlorine gas at 400 mm Hg is decreased to 200 mL at constant temperature. What is the new gas pressure?
1. 400 mm Hg
2. 300 mm Hg
3. 800 mm Hg
4. 650 mm Hg
Under what circumstance might a gas decrease in volume when heated?
1. The gas is held constant at STP.
2. The gas remains under uniform temperature.
3. The gas is placed under increasing pressure.
4. The gas undergoes a decrease in pressure.
Standard temperature and pressure (STP) are defined as
1. 0 °C and 1.0 atm pressure.
2. 0 °C and 273 mm Hg pressure.
3. 0 K and 1.0 atm pressure.
4. 0 K and 760 mm Hg pressure.
Under which of the following sets of conditions will a 0.50 mole sample of helium occupy a volume of 11.2 liters?
1. 298 K and 0.90 atm
2. 273 K and 1.10 atm
3. 373 K and 0.50 atm
4. 273 K and 1.00 atm
What is the equivalent of 423 kelvin in degrees Celsius?
1. –223 °C
2. –23 °C
3. 150 °C
4. 696 °C
Theoretically, when an ideal gas in a closed container cools, the pressure will drop steadily until the pressure inside is essentially that of a vacuum. At what temperature should this occur?
1. 0 °C
2. −460 °C
3. −273 K
4. 0 K
Which of the substances in the table can act as either the solute or the solvent when mixed with 100 grams of water at 20 °C?
1. NH₃
2. C₆H₅COOH
3. MgCl₂
4. CH₃CH₂OH
If the attractive forces among solid particles are less than the attractive forces between the solid and a liquid, the solid will
1. probably form a new precipitate as its crystal lattice is broken and re-formed.
2. be unaffected because attractive forces within the crystal lattice are too strong for the dissolution to occur.
3. begin the process of melting to form a liquid.
4. dissolve as particles are pulled away from the crystal lattice by the liquid molecules.
Water is a polar solvent, while hexane is a nonpolar solvent.
Which of the examples above illustrates a nonpolar solute in a polar solvent?
1. NH₄Cl in water
2. C₁₀H₈ in water
3. C₂H₅OH in hexane
4. CO(NH₂)₂ in hexane
If the solubility of NaCl at 25 °C is 36.2 g/100 g H₂O, what mass of NaCl can be dissolved in 50.0 g of H₂O?
1. 18.1 g
2. 36.2 g
3. 72.4 g
4. 86.2 g
How many moles of HNO₃ are needed to prepare 5.0 liters of a 2.0 M solution of HNO₃?
1. 2.5
2. 5
3. 10
4. 20
The Dead Sea is the saltiest sea in the world. It contains 332 grams of salt per 1000 grams of water. What is the concentration in parts per million (ppm)?

CHEMISTRY CST Practice

Released California State Chemistry Test Questions. © California Department of Education. "Permission is granted in advance for reproduction of these resources for educational purposes. The content must remain unchanged and in its entirety as published by the California Department of Education. "