QUIZ Balancing Chemical Equations

What does the Law of Conservation of Mass state?

• Matter cannot be created or destroyed in a chemical reaction.

• Matter can only be destroyed in a chemical reaction.

• Matter can only be created in a chemical reaction.

• Matter can be created and destroyed in a chemical reaction.

What is the little number after an element in a chemical equation called.
Example: H₂

• Coefficient 
• Subscript
• Atom
• Equation

What are the numbers that you CANNOT change in a chemical equation?

• Coefficients

• Products

• Reactants

• Subscripts

How many atoms of carbon (C) are in C₆H₁₂O₆?

• 3
• 6
• 12
• 24

How many oxygen atoms are in this chemical formula?

• 6 oxygen atoms

• 2 oxygen atoms

• 3 oxygen atoms

• 4 oxygen atoms

Tags

NGSS.MS-PS1-1

How many oxygens are in the following?

3Pb(OH)₄

• 1

• 3

• 4

• 12

How many HCl molecules do you need to balance this equation? 
Mg +  __HCl --->  MgCl₂ + H₂

• 1
• 2
• 3
• 4

Tags

NGSS.MS-PS1-5

Is this equation balanced?

• Yes, it has the same number of each element in both the reactants and the products.

• Yes, but the hydrogens should not have been split in the products.

• No, it doesn't follow the law of conservation.

• No, the hydrogens should not have been split in the products.

Which equation demonstrates the law of conservation of mass?

• Al + 2HCl → AlCl + HB₄

• Al + 2HCl → 2AlCl + H₂

• 2Al + 3HCl → 2AlCl + 3H₂

• 2Al + 6HCl → 2AlCl₃ + 3H₂

Which equation is more correct?

• They are equally correct. They both follow the law of conservation.

• "1" because it follows the law of conservation of mass and is simplified.

• "2" because it is balanced better.