Chemistry Review

In the atom diagram shown, E is pointing to

• An electron
• a proton
• a neutron
• the nucleus

Which of the following is described as the basic unit of matter?

• Element
• Atom
• Molecule
• Compound

In the atom diagram shown, A is pointing to the darker particles, these are known as

• electrons

• protons

• neutrons

• the nucleus

What charge does an electron have?

• Negative
• Positive
• Neutral
• Contrated

A molecule is________

• two ions held together by opposite charges
• smaller than an atom
• can be physically separated into smaller atoms
• more than one atom bonded together by covalent bonds

What is the atomic number of this atom?

• 4
• 5
• 9
• none of the above

An ionic bond forms when 

• Valence electrons are shared
• a sea of mobile electrons surround the cations
• valence electrons are transferred between atoms
• none of the above

Is this image an example of covalent bonding?

• Yes
• No

Using the information provided, determine how many electrons the a Boron atom contains.

• 2.5

• 5

• 6

• 10.81

How are elements organized in the periodic table ?

• Alphabetically

• Based on physical and chemical properties

• Increasing number of electrons

• Most reactive to least reactive