Chem Lab Knowledge Test Answers

Teachers, use these answers to correct the 8th Grade Chemistry Knowledge Assessment included with ChemLab. Use these scores as one element in the overall evaluation of chemistry understanding.

  • PART I - Chemical Names, Symbols and Formulas

    1. Water is the name of the chemical compound H20.

    True

    2. Iron is one of the known naturally occurring elements.
    True

    3. Which of the following chemicals is a mixture?
    air

    4. Hydrogen is:
    an element

    5. Sodium chloride is more commonly known as
    salt or table salt

    6. What is the chemical symbol or formula for Hydrogen?
    H

  • PART II - Periodic Table Basic Information

    7. Elements in the Periodic Table are arranged by common properties and behaviors.

    True

    8. The properties of the compound Sodium Chloride (NaCl) are the same as the properties of the elements Sodium (Na) and Chlorine (Cl).
    False

    9. What chemical information can be found on the Periodic Table?
    all of these

    10. Which of the following would NOT be found on the Periodic Table?
    steel

    11. Acetic Acid (CH3COOH) is comprised of which elements?
    Carbon, Hydrogen and Oxygen

    12. Inert gasses are arranged in what part of the Periodic Table?
    Far right group or column

  • PART III - Chemical Reactions, Reactants and Products

    13. A liquid that forms a gas when heated is an example of a chemical reaction.

    False

    14. When Vinegar (acetic acid CH3COOH) reacts with baking soda (NaHCO3), one of the products is Carbon Dioxide (CO2).
    True

    15. Indicators that a chemical reaction has occurred include:
    all of these

    16. If sodium chloride (NaCl) is mixed with nitric acid (HNO3) what are the likely products?
    sodium hydroxide (NaOH)

    17. In question #16, what are the reactants?
    sodium chloride (NaCl) and nitric acid (HNO3)

    18. Write a chemical reaction equation for the following: Water added to Iron
    H2O + Fe --> Fe2O3 + ??

  • PART IV - Lab Equipment

    19. Name the item in the picture

    flask

    20. Name the item in the picture
    beaker

  • PART V - Describe a chemical reaction situation or scenario

    Include the reactants, expected products, and reaction indicators. samples could include ...

    California Science Content Standards statements: 

    standards statements - background information
     ** 3b. compounds are formed by combining two or more
       different elements. Compounds have properties that
       are different from the constituent elements. 

     **  3d. the states (solid, liquid, gas) of matter
       depend on molecular motion. 

     **  3f. how to use the Periodic Table to identify elements in
        simple compounds 

     **  5a. reactant atoms and molecules interact to form
        products with different chemical properties. 

     **  5d. physical processes include freezing and boiling, in
        which a material changes form with no chemical
        reaction.  

     **  7a. how to identify regions corresponding to metals,
        nonmetals and inert gases. 

     **  7c. substances can be classified by their properties,
        including melting temperature, density, hardness, heat,
        and electrical conductivity.

    Evaluation Rubric Test Your Knowledge Teacher Background Back to ChemLab