Content Benchmark P.8.A.8 Ebert

Students know substances containing only one kind of atom are elements which cannot be broken into smaller pieces by normal laboratory processes. E/S

1st Item Specification: Identify that elements contain only one type of atom.

Depth of Knowledge Level 1

  1. Atoms of an element contain only one type of atom because they each contain the same number of
  1. Protons.
  2. Electrons.
  3. Neutrons.
  4. Nucleons.
  1. The atomic number of an atom is often called its fingerprint because the
  1. electrons are used in bonding.
  2. neutrons hold the nucleus together.
  3. number of protons is identical from atom to atom.
  4. number of protons and electrons never changes.
  1. A student wants to separate atoms of an element into different categories based on the number of protons. You suggest that this isn’t possible because the number of protons
  1. is always the same in an element.
  2. fluctuates wildly.
  3. is different after bonding.
  4. depends on the number of neutrons.
  1. A student wants to separate elements in a mixture based on the number of electrons each contains. You suggest that this isn’t possible because
  1. electrons and protons are attracted to each other.
  2. electrons are repulsed by other electrons.
  3. electrons can vary from atom to atom if they become ions.
  4. electrons are found in the nucleus.
  1. The modern periodic table is based on elements being arranged by their atomic number. This is because elements arranged according to atomic number have one more
  1. proton than the element before it.
  2. neutron than the element before it.
  3. anion than the element before it.
  4. cation than the element before it.

Depth of Knowledge Level 2

  1. Oxygen has an atomic number of 8 while chlorine has an atomic number of 17. The difference between oxygen and chlorine is that
  1. oxygen has double the number of electrons than chlorine.
  2. chlorine has 11 more protons than oxygen.
  3. chlorine has 9 more protons than oxygen.
  4. oxygen loses protons in physical changes.
  1. Isotopes are atoms of an element that contain varying numbers of neutrons in the nucleus. Which of the following is true?
  1. C-12 has more electrons than C-14.
  2. C-12 has more protons than C-14.
  3. C-12 has fewer electrons for bonding than C-14.
  4. C-12 and C-14 have the same number of protons.
  1. The mass number of an element is the number of protons and neutrons added together. Which of the following is true for nitrogen (mass number 14, atomic number 7) and oxygen (mass number 16, atomic number 8)?
  1. Nitrogen contains more electrons than oxygen.
  2. Nitrogen contains one less proton than oxygen.
  3. Nitrogen contains four more protons than oxygen.
  4. Nitrogen contains two less protons than oxygen.
  1. The mass number of an element is the number of protons and neutrons added together. Which of the following is true for carbon-13 (atomic number 6) and nitrogen-15 (atomic number 7)?
  1. Nitrogen contains more electrons than carbon.
  2. Nitrogen has 8 neutrons and carbon has 7 neutrons.
  3. Nitrogen contains two more protons than carbon.
  4. Nitrogen contains one less proton than carbon.

Constructed Response P.8.A.8

  1. The diagram below depicts an apparatus, where an electric current is passed through a beaker of water and two separate gases are collected. Use this diagram to answer the following questions.

  1. Design a laboratory method for identifying the nature of the gases.
  1. Describe the type of reaction illustrated by the diagram.
  1. Can the two gases be further broken down? Support your answer with evidence and explain why only two gases could be formed in this process.

Content Benchmark P.8.A.8

Students know substances containing only one kind of atom are elements which cannot be broken into smaller pieces by normal laboratory processes. E/S

Answers to Sample Test Questions

  1. A, DOK Level 1
  2. C, DOK Level 1
  3. A, DOK Level 1
  4. C, DOK Level 1
  5. A, DOK Level 1
  6. C, DOK Level 2
  7. D, DOK Level 2
  8. B, DOK Level 2
  9. B, DOK Level 2

Constructed Response 3-point Answers and Score Rubrics:

3 points / Response addresses all parts of the question clearly and correctly.
Student response indicates that the gases must be oxygen and hydrogen, and that glowing splint can be inserted into the test tubes If a loud popping sound is heard, then the gas is hydrogen, or if the splint re-ignites, then the gas is oxygen. Student responses also indicate that the process is decomposition and the gases are pure elements which cannot be further broken down by this method.
2 points / Response addresses all parts of the question and includes only minor errors.
1 point / Response does not address all parts of the question.
0 point / Response is totally incorrect or no response provided.