8th Grade: Chemistry Unit Review

For a chemical equation to be balanced, reactants and products must have what?

• More atoms in the product than atoms in the reactant

• Equal number of compounds

• Equal number of molecules

• Equal number of atoms of each element

Tags

NGSS.MS-PS1-5

True or False: A "group" on the periodic table is also known as a "family".

• True

• False

The number of valence electrons an atom has can be determined by looking at what?

• The atom’s period number
  
• The atom’s group/family number
  
• The atom’s atomic number
  
• The atom’s atomic mass
  

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

The number of an atom's valence electrons directly affects the atom's what?

• Atomic mass
  
• Physical properties
  
• Reactivity
  
• Atomic number
  

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

In an atom, which of the following has a NEGATIVE charge?

• Protons

• Neutrons

• Electrons

• Protons & neutrons

Tags

NGSS.MS-PS1-1

Which of the following is the definition of a chemical change?

• A new substance is produced
  
• Matter is lost during a chemical change
  
• New matter is created

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Elements in the same________ have similar chemical & physical properties.

• Family
• Group
  
• Neither answer is correct
  
• Both answers are correct

To follow The Law of Conservation of Mass, an element's atoms in the product must do what?

• Equal number of atoms in the reactant

• Be less than its number of atoms in the reactant

• Be greater than its number of atoms in the reactant

Tags

NGSS.MS-PS1-5

An element from Group 1 is most likely to react with an element from Group ___

• 18
  
• 1
• 17
• 2

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

True or False: As a result of a chemical reaction, atoms are changed into different atoms. 

• True
• False- atoms are simply rearranged
  

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5