Chemical reaction quiz

What is the law of conservation of mass?

• In a closed system, the mass of the reactants is the same as the mass of the products.
• In an open system, the mass of the reactants is the same as the mass of the products.
• In a synthesis reaction, the mass of the product is always greater than the mass of the reactants.
• By US law, mass lands must be conserved.

Identify the coefficient(s):
5 K₃PO₄

• 5
• 3 and 4
• 1

Identify the subscript:
5 CuCl₂

• 5
• 2

What do coefficients tell us?

• How many atoms of a specific element in a compound.
• How many units of a compound/element.
• How many times the compound/element reacts in a reaction.
• How important the compound/element is to a chemical reaction.

What do subscript tell us?

• How many atoms of a specific element in a compound.
• How many units of a compound/element.
• How many times the compound/element reacts in a reaction.
• How important the compound/element is to a chemical reaction.

How many atoms total?
3 AgBr

• 2
• 3
• 4
• 6

How many Ag atoms in 1 Ag₃PO₄?

• 1
• 3
• 4

How many P atoms in 1Ag₃PO₄?

• 1
• 3
• 4

Identify the reactants in this reaction. The equation may or may not be balanced.
K₃PO₄ + HCl --> KCl + H₃PO₄

• K₃PO₄ and KCl
• K₃PO₄ and HCl
• HCl and KCl
• HCl and K₃PO₄

Identify the products in this reaction. The equation may or may not be balanced.
K₃PO₄ + HCl --> KCl + H₃PO₄

• H₃PO₄ and KCl
• K₃PO₄ and KCl
• HCl and KCl
• HCl and K₃PO₄