Law of Conservation of Matter

Which side of a chemical equation is the reactant side?

• Left (before the yields sign)
• Right (after the yields sign)

Which side of a chemical equation os the product side?

• Left (before the yields sign)
• Right (after the yields sign)

The Law of Conservation of matter states that the total amount of matter ______________ after it undergoes change.

• disappears
• stays the same
• weighs less
• explodes

An oreo cookie weighs 20 grams.  It gets crushed into crumbs for a recipe.  How much do its crumbs weigh?

• 15 grams
• 25 grams
• 20 grams

Based on the Law of Conservation of Matter, describe the relationship between the mass of the reactants and the mass of the products.

• The mass of the products is always greater than the mass of the reactants.

• The mass of the reactants is less than the mass of the products.

• The mass of the reactants equals the mass of the products.

• The mass of the reactants is greater than the mass of the products.

If a chemical reaction occurs in an open system (not contained), what might happen to the measurable mass of the products when compared to the reactants?

• the measurable mass might decrease because any gas produced can escape (the actual mass would stay the same)

• the mass would increase because mass was created

• the measurable mass would stay the same because nothing would be able to leave the system.

• it depends on the type of reaction

In a balanced chemical equation, if there are 4 Hydrogen in the reactants, how many Hydrogen should be in the product?

• 1

• 2

• 3

• 4

In a reaction A + B ----> C.

Reactant A has 5g and product C has 9g.

How many grams does reactant B should have?

• 4g

• 5g

• 9g

• 14g

A pile of 500 pieces of paper has a mass of 250 grams. If all the sheets of paper are the same and it is split into five equal piles, what would be the mass of each pile?

• 250 grams

• 500 grams

• 2500 grams

• 50 grams

Grinding an effervescent tablet into powder increases the rate of reaction due to increase of

• concentration

• total surface area

• temperature

• size