The diagram above is a model of a molecule of methane. What is the formula for methane?
CH8
C8H4
CH4
C8H8
2. Multiple Choice
3 minutes
1 pt
2Mg + O2 → 2MgO In the equation above, how many atoms are in the oxygen molecule?
2
0
1
3
3. Multiple Choice
3 minutes
1 pt
The formula below represents the most common carbohydrate known as Glucose. Glucose is synthesized by Chlorophyll in plants as they use carbon dioxide from the air and sunlight as an energy source during the process of photosynthesis. C6H12O6 What information can be determined from the chemical formula?
The structural arrangement of the atoms in a glucose molecule.
The color of a glucose molecule.
The size of a glucose molecule.
The number of atoms of each element in a glucose molecule.
4. Multiple Choice
3 minutes
1 pt
Which of the following formulas contain the same number of oxygen atoms? 1. Mg(NO)2 2. NH4NO2 3. Ca(ClO2)2 4. Co(NO3)2
Formulas 1 and 2
Formulas 2 and 4
Formulas 1, 2, and 3
Formulas 1, 2, and 4
5. Multiple Choice
3 minutes
1 pt
How many atoms are in one molecule of baking soda, NaHCO3?
4
5
3
6
6. Multiple Choice
3 minutes
1 pt
A student placed 2 grams of baking soda in a balloon, and 100 mL of vinegar in a Erlyenmeyer flask. After stretching the balloon across the neck of the flask, the student raised it to drop the baking soda into the flask. He immediately observed foaming bubbles in the flask and the balloon began to expand. The student concluded that -
Only a physical change was occuring
The baking soda and vinegar were products of a chemical reaction
The gas was oxygen
The bubbles indicated that a chemical change was occuring
7. Multiple Choice
3 minutes
1 pt
During an investigation, students dropped a tarnished penny into a solution a acetic acid and sodium chloride. Tiny bubbles formed around the penny, and the penny was less tarnished after two minutes of soaking in the acetic acid and sodium chloride solution. The student inferred that a chemical reaction occured. What evidence supports the students' inference?
The penny experienced a color change, and a gas was produced.
The penny experienced a color change, and a precipitate was formed.
The penny experienced a color change and is in a new state of matter.
The penny experienced a color change and produced light.
8. Multiple Choice
3 minutes
1 pt
Students in a science lab conducted an investigation. Students recored the following observations. Substance 1 produced light when burned. Substance 2 dissolved in water. Substance 3 melted at 100⁰ C. Substance 4 formed a precipitate. Which substances produced a chemical change?
Substances 1 and 2
Substances 1 and 3
Substances 1 and 4
Substances 2 and 3
9. Multiple Choice
3 minutes
1 pt
Which of the following equations follows the law of conservation of mass?
3H2O → 3H2 + 3O2
C2H4 + 3O2 → 2CO2 + 2H2O
C + 4H2 → CH4
2Na + Cl → NaCl
10. Multiple Choice
3 minutes
1 pt
How can a student determine that a chemical reaction demonstrates the law of conservation of mass?
Students can compare the products and reactants to determine if the same molecules are present before and after the reaction.
Students can compare the products and reactants to determine if the same number of atoms of each element are present before and after the reaction.
Students can compare the products and reactants to determine if the same number of molecules are present before and after the reaction.
Students can compare the products and reactants to determine if the same elements are present before and after the reaction.
11. Multiple Choice
3 minutes
1 pt
In a chemical equation, it is true that -
the reactants and products can have different numbers of atoms for each element.
there can be different elements on the reactants side and the product side.
an element or compound must be accompanied by a phase change.
the coefficients indicate the number of molecules of each reactant used and the number of molecules of each product made.
12. Multiple Choice
3 minutes
1 pt
What is the correctly balanced chemical equation for the formation of rust, Fe2O3, forming when oxygen, O2 reacts with iron, Fe?
O2 + Fe → Fe2O3
3O2 + 4Fe → 2Fe2O3
3O2 + 2Fe → 2Fe2O3
2O2 + 4Fe → 2Fe2O3
13. Multiple Choice
1 minute
1 pt
What conclusion can you make about the elements shown above?
Phosphorus has more valence electrons than nitrogen.
Carbon has fewer protons in its nucleus than nitrogen.
Phosphorus is more like silicon than it is like nitrogen.
Aluminum is smaller than carbon.
14. Multiple Choice
1 minute
1 pt
Refer to the Venn diagram above. Which of the following traits do Element I and Element II have in common?
The same atomic number
The same atomic mass
The same number of energy levels
The same number of valence electrons
15. Multiple Choice
1 minute
1 pt
Refer to the Venn diagram above. Which of the elements would have the most similar chemical properties as Element I?
Tantalum
Scandium
Potassium
Strontium
16. Multiple Choice
1 minute
1 pt
Which of the atom models above represents a stable atom that will not react?
Model A
Model B
Model C
Model D
17. Multiple Choice
1 minute
1 pt
Based on what you know about the organization of the Periodic Table, which two elements shown above would have the most similar chemical properties?
Sodium and Magnesium
Potassium and Calcium
Potassium and Magnesium
Sodium and Potassium
18. Multiple Choice
1 minute
1 pt
The most reactive metal is one with -
4 valence electrons
1 valence electron
2 valence electrons
3 valence electrons
19. Multiple Choice
1 minute
1 pt
When determining an element's chemical properties, the most important subatomic particle to look at is -
protons
valence electrons
neutrons
positrons
20. Multiple Choice
1 minute
1 pt
In order to perform an experiment, a chemist needs an element that has similar properties of potassium (K) but has a lower atomic mass. Which element should the chemist select for the experiment?
Rubidium (Rb)
Sodium (Na)
Magnesium (Mg)
Calcium (Ca)
21. Multiple Choice
1 minute
1 pt
Which of the following groups in the Periodic Table is made from reactive metals?
Group 1
Group 6
Group 17
Group 18
22. Multiple Choice
3 minutes
1 pt
Which of the following groups in the Periodic Table is made from non-reactive elements?
Group 1
Group 4
Group 17
Group 18
23. Multiple Choice
3 minutes
1 pt
Using the Periodic Table, which of the following groups of elements has the smallest atomic number in Period 4?
Group 1
Group 4
Group 17
Group 18
24. Multiple Choice
3 minutes
1 pt
Atoms of which of the following elements have the most similar chemical properties as Cadium (Cd) atoms?
Zinc (Zn)
Gold (Au)
Copper (Cu)
Silver (Ag)
25. Multiple Choice
1 minute
1 pt
Refer to the image above. Which of these is NOT found in the nucleus of an atom?
Neutrons
Protons
Atomic mass
Electrons
26. Multiple Choice
1 minute
1 pt
Which of the atom models above represents a reactive metal?
Model A
Model B
Model C
Model D
27. Multiple Choice
3 minutes
1 pt
Which of the following is the atomic mass of the atom represented in the above graphic?
17 amu
16 amu
33 amu
32 amu
28. Multiple Choice
1 minute
1 pt
Which of the following elements is represented by the above graphic?
Sulfur
Chlorine
Argon
Arsenic
29. Multiple Choice
3 minutes
1 pt
Which of the following is the atomic number of the atom represented in the above graphic?
16
17
18
33
30. Multiple Choice
3 minutes
1 pt
Which of the following is the number of valence electrons in the atom represented above?