Atoms

What is the atomic mass of a nitrogen atom?

• 12.011

• 14.007

• 15.999

• 1.008

What is the smallest unit of matter?

• Molecule

• Atom

• Compound

• Element

What is an isotope?

• Atoms of the same element that have different numbers of neutrons.

• Atoms of different elements that have the same number of protons.

• Atoms that have the same mass but different charges.

• Atoms that are chemically identical but physically different.

What are the two sub-atomic particles that make up the nucleus of an atom?

• Electron and Proton

• Proton and Neutron

• Neutron and Positron

• Proton and Electron

How many neutrons does a titanium atom have if its atomic mass is 47.87 and its atomic number is 22?

• 22

• 25

• 25.87

• 27

What is the periodic table?

• A tabular arrangement of elements organized by increasing atomic number.

• A list of all known chemical compounds.

• A graphical representation of chemical reactions.

• A collection of all known isotopes of elements.

How many known elements are there in the periodic table?

• 116

• 118

• 120

• 122

What is the charge of an electron?

• Positive

• Neutral

• Negative

• Variable

What is the role of neutrons in an atom?

• Neutrons help stabilize the nucleus and prevent protons from repelling each other.

• Neutrons are responsible for the chemical properties of an atom.

• Neutrons determine the atomic number of an element.

• Neutrons are involved in the formation of chemical bonds.

What is the charge of a proton?

• Negative

• Neutral

• Positive

• Variable