What is at the center of an atom?

• A cloud of electrons.

• A dense, negatively charged nucleus containing electrons and neutrons.

• A dense, positively charged nucleus containing protons and neutrons.

• Photons

Tags

NGSS.HS-PS1-8

What surrounds the nucleus of an atom?

• Photons
• A cloud of negatively charged electrons.

• Neutrons
• A cloud of positively charged electrons.

What charge do protons have?

• 0

• 1-

• 1/2

• 1+

What charge do electrons have?

• 0

• 1-

• 1/2

• 1+

What charge do neutrons have?

• 0

• 1-

• 1/2

• 1+

True or false: Objects with opposite charges attract one another.

• True

• False

What are valence electrons?

• Valence electrons are the electrons in the nucleus of an atom.
• Valence electrons are the electrons in the innermost shell of an atom.
• Valence electrons are the electrons that determine the charge of an atom.
• Valence electrons are the electrons in the outermost shell of an atom.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which group in the Periodic Table contains elements that hardly react at all?

• Alkali Metals
• Transition Metals
• Noble Gases
• Halogens

Where on the Periodic Table are nonmetals generally found?

• Middle side
• Bottom side
• Top side
• Right side

How do the compositions of mixtures differ from those of substances?

• Substances have a fixed composition, while mixtures can vary in their components.

• Mixtures have a fixed composition, while substances can vary in their components.
• Mixtures are always in a gaseous state, while substances can be solid, liquid, or gas.
• Mixtures contain only one substance, while substances can have multiple components.