Unit 1 Review

Which of the following best describes an electron?

• It has no charge and about the same mass as a proton.
• It has a negative charge and much less mass than a proton. 
• It has a positive charge and much more mass than a neutron.
• It has a negative charge and about the same mass as  a neutron.

An atom of a certain element has 36 protons, 36 electrons, and a mass number of 84. At room temperature this element is stable. How many neutrons are in this atom? 

• 36 neutrons
• 84 neutrons
• 48 neutrons

A model of a beryllium atom is shown below. What types of particles are found in the cloud surrounding the atom's nucleus? 

• Positively charged particles and negatively charged particles
• Negatively charged particles only 
• Neutral particles and positively charged particles 
• Positively charged particles only

Which group is more reactive, group 18 or group 1?

• group 1
• group 18

How many valence electrons are in an atom of each element in Group 15 in the periodic table? Enter only a number, no letters or words.

A student is studying the ways different elements are similar to one another. Diagrams of atoms from four different elements are shown in the image.

Which two atoms are of elements in the same group in the periodic table?

• Atom 1 and Atom 2

• Atom 1 and Atom 4

• Atom 2 and Atom 3

• Atom 3 and Atom 4

You can identify the number of protons by looking at the ____________ on the periodic table.

• Atomic mass
• Atomic number
• Atomic Symbol
• Impossible

Elements in the same period/row have the same--

• # of valence electrons

• # of protons

• # of energy shells

• # of neutrons

The mass of the atom is located ---

• in the Nucleus

• in the Electron Cloud

• protons only

• neutrons only

These two subatomic particles contribute to the mass of the atom.

• Protons and Electrons

• Protons and Neutrons

• Electrons and Neutrons