Quiz on Basic Chemistry Concepts

What is the simplest form of a substance?

• An element

• An atom

• A molecule

• A compound

What is an atom composed of?

• Only one type of element

• Subatomic particles called electrons, protons, and neutrons

• Multiple elements

• Only protons

How are elements recognized in the periodic table?

• By their color

• By their relative atomic mass in addition to the atomic number

• By their size

• By their weight

How many elements are there in total?

• 92

• 118

• 150

• 200

How many different kinds of atoms are there in nature?

• 92

• 118

• 150

• 200

What is the difference in size between elements and atoms?

• Elements are usually smaller and lighter than atoms

• Elements are usually bigger and heavier than atoms

• Elements and atoms are the same size

• Atoms are bigger and heavier than elements

What do atoms of the same element usually contain?

• Different atomic numbers

• Same atomic number but different mass number due to isotopes

• Same mass number but different atomic number

• Different numbers of electrons

What does the Bohr theory of atomic structure assume about the atom?

• The atom consists of a neutron as nucleus, with electrons moving in random orbits.

• The atom consists of a proton as nucleus, with electrons moving in distinct circular orbits.

• The atom consists of a proton as nucleus, with electrons moving in elliptical orbits.

• The atom consists of a neutron as nucleus, with electrons moving in elliptical orbits.

According to the Bohr theory, what corresponds to a specific quantized energy state?

• The shape of the electron's orbit.

• The speed of the electron.

• Each distinct circular orbit of the electron.

• The size of the proton.

What is an atom?

• The largest particle of an element that has different properties from the element.

• The smallest particle of an element that has the same properties of the element.

• A particle that does not have any properties of the element.

• A particle that is larger than a molecule.