Atoms, Mixtures and Chemical Reactions

What is the smallest building block of matter?

• Compounds

• mixtures

• atoms

• pizza

Which choice would be a molecule?

• O

• H

• Au

• H₂

Which of the following is an element?

• H₂O

• C₁₂H₂₂O₁₁

• NaCl

• H₂

Tags

NGSS.MS-PS1-1

Liquid becomes a solid at the ________ point.

• melting

• freezing

• boiling

• evaporating

Which of the following is a sign that a chemical reaction has occurred?

• change in shape
• melting
• formation of a gas
• dissolving

How many hydrogen atoms are in this chemical formula: 

• 4 hydrogen atoms
• 1 hydrogen atom
• 2 hydrogen atoms
• 3 hydrogen atoms

Tags

NGSS.MS-PS1-1

How is a compound different from a mixture?

• Mixtures are created through physical changes; compounds are created through chemical reactions.
• Compounds are created though physical changes; mixtures are created through chemical reactions.
• Mixtures on average are heavier than compounds.
• Compounds, on average are heavier than mixtures.

The positive particles of an atom are...

• electrons

• positrons

• neutrons

• protons

The central region of an atom where its neutrons and protons are is the...

• nucleus

• electron cloud

• core

• center

Particles in an atom that are neutral and have no charge are the...

• negatrons

• electrons

• neutrons

• protons