Braden Unit 2 Review 23

How many atoms are in the following chemical formula?
2H₂O₂

• 4
• 6
• 8
• 10

How many elements are in the following chemical formula:
H₂COFe

• 3
• 6
• 4
• 5

How many atoms are in the following chemical formula?
Cl₂C₂O

• 3
• 5
• 4
• 6

How many atoms are in the following chemical formula?
2KP₂O₃

• 9
• 10
• 12
• 11

How many atoms are in the following chemical formula?
Fe (OH)₃

• 5
• 6
• 7
• 8

How many elements are in the following chemical formula?
FeH₃O₃CoS₂

• 5
• 4
• 6
• 7

(8.5D) The chemical formula for sodium sulfate is Na₂SO₄. How many sulfur atoms are in the formula for sodium sulfate?

• 1
• 2
• 6
• 7

(8.5D) Which information could a student determine from only the chemical formula of a protein? 

• The color of the protein
• The number of molecules in each sequence that makes up a protein
• The physical arrangement of atoms in the structure of the protein
• The number of atoms of each element in the protein

(8.5E)A student observes some sugar as it is heated and burns. The student concludes that a chemical reaction has occurred. Which of the following observations about the burning sugar provides evidence of a chemical reaction?

• Heat is added to the sugar crystals.
• The sugar melts and becomes a liquid.
• The temperature of the sugar increases
• Gas is produced as the sugar turns black.

CaCO₃ ---> CaO + CO₂
In the chemical reaction shown above, the products are best classified as-- (6.5C)

• two elements
• one element and one compound
• two compounds
• two compounds and one element