Conservation of Mass and Chemical Reactions

What is the first reactant in the equation LiO + MgCl₂ → 2LiCl + MgO?

• LiO

• MgCl₂

• LiCl

• MgO

Tags

NGSS.MS-PS1-1

In the equation 2H₂ + O₂ → 2H₂O, what does the coefficient '2' in front of H₂ indicate?

• 2 molecules of H₂

• 2 atoms of H

• 2 ions of H

• 2 moles of H

Tags

NGSS.MS-PS1-5

How many oxygen atoms are on the product side in the equation 2AlCl₃ + 3Na₂CO₃ → Al₂(CO₃)₃ + 6NaCl?

• 3

• 6

• 9

• 12

Tags

NGSS.MS-PS1-1

Name the first product in the equation LiO + MgCl₂ → 2LiCl + MgO: __________.

• LiO

• MgCl₂

• LiCl

• MgO

In the equation 2K₃N + 3CaCrO₄ → Ca₃N₂ + 3K₂CrO₄, how many potassium atoms are on the reactant side?

• A) 2

• B) 3

• C) 6

• D) 9

Give the formula for the second reactant in the equation 2K₃N + 3CaCrO₄ → Ca₃N₂ + 3K₂CrO₄: __________.

• K₃N

• CaCrO₄

• Ca₃N₂

• K₂CrO₄

Tags

NGSS.MS-PS1-5

What does a subscript in a chemical formula indicate?

• Number of molecules

• Number of atoms

• Number of ions

• Number of moles

In the equation Fe₂O₃ + 3C → 2Fe + 3CO, how many total atoms are on the reactant side?

• A) 5

• B) 6

• C) 7

• D) 8

Tags

NGSS.MS-PS1-1

Name the first reactant in the equation 2AlCl₃ + 3Na₂CO₃ → Al₂(CO₃)₃ + 6NaCl: __________.

• AlCl₃

• Na₂CO₃

• Al₂(CO₃)₃

• NaCl

In the equation 2H₂ + O₂ → 2H₂O, what does the arrow indicate?

• A) Reactants

• B) Products

• C) Yields

• D) Coefficients