Chemical Reactions and Equations

What is the coefficient of the oxygen molecule in the elephant toothpaste equation?
2 H₂O₂ -> 2 H₂O + O₂

• 0
• 1
• 2
• 4

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

What do you call the substances on the left side of a chemical equation?

• yield
• products
• reactants
• compounds

Tags

NGSS.MS-PS1-1

Which is the correct atom count for the reactant side of the chemical equation?
CH₄ + 2 O₂ -> CO₂ + 2 H2O

• C=4
  H=4
  O=4
• C=1
  H=4
  O=2
• C=1
  H=4
  O=2
• C=1
  H=4
  O=4

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-1

Which contains the greatest number of elements?

• 5CH₄
• Fe₂O₃
• C₆H₁₂O₆
• C₈H₁₀N₄O₂

Tags

NGSS.MS-PS1-1

Which contains the greatest number of atoms?

• 5CH₄
• Fe₂O₃
• C₆H₁₂O₆
• C₈H₁₀N₄O₂

Tags

NGSS.MS-PS1-1

How are chemical bonds formed?

• by sharing, giving, or taking electrons from another atom
• through radioactive decay
• by losing or gaining neutrons in the nucleus
• by exchanging protons with another atom

Tags

NGSS.MS-PS1-1

What is the ratio of iron atoms to oxygen atoms in the compound for rust (Fe₂O₃)?

• 2:3
• 3:2
• 1:1
• not able to be determined

Tags

NGSS.MS-PS1-1

A subscript tells you...

• the # of atoms in the entire equation
• the # of elements in the equation
• the # atoms of the element it sits behind
• the # of compounds present

Tags

NGSS.MS-PS1-1

A coefficient tells you...

• the # of atoms in the entire equation
• the # of elements in the equation
• the # atoms of the element it sits behind
• the # of molecules of that substance

Tags

NGSS.HS-PS1-7

When two substances were combined, bubbles were produced and the temperature dropped.  This most likely means that:

• a chemical reaction took place
• the two substances had low boiling points
• one substance dissolved in the other
• the two substances are non-reactive

Tags

NGSS.MS-PS1-2