WorksheetsLaw of Conservation of Mass
Total questions: 17
Worksheet time: 42mins
Name
Class
Date
1.
What is the Law of Conservation of mass?
a)
Mass is created in a chemical reaction
b)
Mass is created in a physical change
c)
New chemicals formed from a chemical reaction have a larger overall mass than the original reactants
d)
Mass is never created or destroyed
2.
In a reaction A + B ----> C, reactant A has 5g and product C has 9g. How many grams does reactant B should have?
a)
4g
b)
5g
c)
9g
d)
14g
3.
If a reaction starts with a total 75g of reactants it should produce
a)
a total of 40g of products
b)
a total of 75g of products
c)
a total of 180 g of products
d)
None of the above
4.
In the reaction AB-----> A + B reactant AB has 12g and product B has 5g. How many grams should product A have?
a)
17g
b)
2g
c)
7g
d)
None of the above
5.
Bob puts 200 grams of ice into a pitcher with 900 grams of water. He gets distracted and comes back later to find that the ice has melted in the water. How many grams of water does Bob now have in the pitcher?
a)
200 g
b)
700 g
c)
1,100 g
6.
This type of system allows matter to flow freely in and out...
a)
Closed System
b)
Open System
7.
A boiling pot with a lid on it to keep in the energy is what type of system?
a)
Closed System
b)
Open System
8.
Which of these is not a chemical reaction?
a)
Burning of wood
b)
Milk going bad
c)
Mixing vinegar and baking soda
d)
Melting of ice
9.
What types of systems are there?
a)
Mechanical and Electrical Systems
b)
Inside and Outside Systems
c)
Open and Closed Systems
d)
Human and Machine Systems
10.
What will weigh more when a chemical change is complete? The reactants before the chemical reaction, or the product after the reaction is complete?
a)
They both will weigh the same
b)
The product always weighs more than the reactant
c)
The reactant will weigh more than the product
d)
They both will loose mass after the reaction
11.
Since gasses weigh nothing, when they are produced in a reaction they do not have to be accounted for.
a)
True
b)
False
12.
12g of Carbon react with 16g of Oxygen, how much carbon monoxide (CO) is formed?
a)
28 g
b)
4g
c)
30g
d)
12g
13.
In the reaction shown by the equation, 252 grams of FeCl2 and 70 grams of Cl2 are consumed.
2FeCl2+ Cl2--> 2FeCl3
How many grams of FeCl3 are produced?
2FeCl2+ Cl2--> 2FeCl3
How many grams of FeCl3 are produced?
a)
161 grams
b)
182 grams
c)
322 grams
d)
392 grams
14.
When CaCO3 is heated, it forms CaO and CO2. Which of these statements best describes the mass of the products if 100 g of CaCO3 is heated?
a)
The difference in the products’ masses is equal to the mass of the CaCO3
b)
The sum of the products’ masses is less than the mass of the CaCO3
c)
The mass of each product is equal to the mass of the CaCO3
d)
The sum of the products’ masses equals the mass of the CaCO3
15.
24 g of magnesium reacts with 38 g of fluorine to produce _____ g magnesium fluoride
a)
62
b)
38
c)
24
d)
14
16.
32 g of Oxygen completely reacts with 8 g of Hydrogen to produce _____ g Water
a)
8
b)
12
c)
24
d)
40
17.
In a reaction A + B ----> AB, reactant A has 4g and product AB has 10g. How many grams does reactant B should have?
a)
4g
b)
5g
c)
6g
d)
14g
100 %
