Semester 1 Review

The pH range of acid rain in Georgia varies from 4.22 to 4.40. According to this data, what is the pH of the most acidic rainfall in Georgia?

• 4.22
• 4.30
• 4.35
• 4.40

Which is true about real gases?

• They do not obey all the assumptions of the kinetic-molecular theory.
• They consist of particles that do not occupy space.
• They cannot be condensed
• They cannot be created in scientific laboratories.

Atoms are composed protons, neutrons, and electrons. The table below shows these subatomic components and the charges that belong to them.

Based on the information in the table, which of the following is true?

• Protons and neutrons are attracted to one another.
• Neutrons and electrons repel each other.
• Electrons and protons are attracted to one another.
• All subatomic particles repel one another.

Courtney wants to test an unknown chemical solution. What test should Courtney perform to determine whether the chemical is an acid or base?

• Test the solution by increasing its temperature.
• Test the solution by calculating its density.
• Test the solution by tasting it.
• Test the solution's pH by using litmus paper.

Why should a chemical equation be balanced?

• to show that the reactants are compounds
• to show metals from nonmetals
• to show ionic compounds
• to show the law of conservation of mass

The picture below represents an atom and its subatomic particles.

Which letter in the picture represents an electron?

• w
• x
• y
• z

What are the charged particles that form when atoms gain or lose electrons?

• bonds
• ions
• atoms
• elements

The density of four unknown liquids is given in the following table.
A  student places a small, solid cube in each of the liquids The cube has a mass of 10 grams and a volume of 8 cubic centimeters In which of the liquids will the cube float?

• in liquid 4 only
• in liquid 3 and 4 only
• in liquid 2, 3, and 4 only
• in all liquids

Which hypothesis describes the behavior of molecules when a substance changes from a gas to a liquid?

• The average speed of the molecules increases, because they have lower energy in the liquid state.
• The average speed of the molecules decreases, because they have lower energy in the liquid state.
• The average speed of the molecules decreases, because they have higher energy in the liquid state.
• The average speed of the molecules increases, because they have higher energy in the liquid state.

Use the periodic table to determine which of the following contains 20 protons and 19 electrons.

• ion of calcium
• ion of potassium
• neutral calcium atom
• neutral potassium atom