Protons and Valence Electrons

When trying to identify an unknown element, a scientist determines what other elements reacts with chemically. Which property of the unknown element determines the other element it reacts with?

• The total number of neutrons in the unknown element

• The total number of particles in the nucleus of the unknown element

• The number of protons in the nucleus of the unknown element

• The number of valence electrons in the unknown element

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What part of the atom determines the identity of an atom?

• Electrons

• Neutrons

• Protons

• Nucleus

What part of the atom determines the chemical properties or reactivity?

• Protons

• Electrons

• Valence Electrons

• Energy levels

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which statement accurately describes atoms of Oxygen?

• Oxygen atoms have 20 protons

• Oxygen atoms have 8 valence electrons

• Oxygen atoms have 16 neutrons

• Oxygen atoms have 8 electrons

A student is studying calcium, a highly reactive element that humans need for strong bones. Which characteristics of calcium is most closely related to its chemical reactivity?

• The 20 protons in each atom of calcium

• The density of calcium

• The atomic number

• The two valence electrons in each atom of calcium

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What groups are the most reactive metals?

• 2 and 3

• 1 and 18

• 1 and 2

• 16 and 17

What groups are the most reactive non metals?

• 1 and 2

• 16 and 17

• 2 and 17

• 1 and 16

Which model represents the most reactive atom?

• 
• 
• 
• 

Tags

NGSS.MS-PS1-1

Which of the following characteristics is similar for fluorine and iodine?

• Number of protons

• Number of neutrons

• Number of orbitals

• Number of valence electrons

How many valence electrons are found in atoms of group 14?

• 4
• 3
• 14
• 16