Chemistry Midterm Review Fall '20

An atom of which element has 37 protons, 48 neutrons and 1 valence electron?

• Neon (Ne)

• Carbon (C)

• Rubidium (Rb)

• Sodium (Na)

Tags

NGSS.MS-PS1-1

An atom of which element is represented by this model?

• Neon (Ne)

• Boron (B)

• Nitrogen (N)

• Carbon (C)

Tags

NGSS.MS-PS1-1

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

The atoms of a certain element each contain 9 protons and 7 valence electrons. Which statement correctly identifies this element and describes the chemical reactivity?

• The element is oxygen, and is highly reactive.

• The element is fluorine, and is highly reactive.

• The element is oxygen, and is not very reactive.

• The element is fluorine, and is not very reactive.

A chemist is identifying the elements present in a sample of seawater. What characteristic of an element's atoms always determines the element's identity?

• The number of electrons

• The number of neutrons

• The number of protons

• The number of valence 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

What groups are the most reactive metals?

• 2 and 3

• 1 and 18

• 1 and 2

• 16 and 17

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2