WorksheetsLaw of Conservation of Mass
Total questions: 10
Worksheet time: 23mins
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.
The number in front of a compound or element is a
a)
Subscript
b)
Coefficient
c)
Superscript
d)
Charge
4.
The number to the lower side of an element is a
a)
Subscript
b)
Superscript
c)
Coefficient
d)
Charge
5.
Matter can not be created nor destroyed: it can only be
a)
Destroyed a little bit
b)
Invisible
c)
Transformed, changed
d)
None of the above
6.
Which is Chemical Equation is Balanced?
a)
CH₄+O₂------CO₂+2H₂O
b)
H₂+O₂-----2H₂O₄
c)
4Al+3O₂-----2Al₂O₃
7.
Is this equation balanced or unbalanced?
2Fe2O3 + 3C --> 4Fe + 3 CO2
2Fe2O3 + 3C --> 4Fe + 3 CO2
a)
balanced
b)
unbalanced
8.
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
9.
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
10.
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
100 %
