Protons, neutrons and electrons

Grade 8 Science Worksheet

NameDate

Circle the best answer, or write your answer on the line.

  1. A potassium atom has atomic number 19 and mass number 39. How many neutrons does it have, Ari?

  2. A zinc atom has atomic number 30 and mass number 64. How many neutrons does it have, Bo?

  3. A silver atom has atomic number 47 and mass number 107. How many neutrons does it have, Esme?

  4. Read this first

    Table (IUPAC data)

    Atomic number, symbol, name. 6 C carbon; 7 N nitrogen; 8 O oxygen; 9 F fluorine; 13 Al aluminum; 16 S sulfur.

  5. An atom has 8 protons and 8 neutrons. Using the table, which element is it, Jun?

    • Sulfur, element 16
    • Oxygen
    • You can't tell without the electrons
    • It depends on the neutrons
  6. Atomic number, symbol, name. 26 Fe iron; 29 Cu copper; 30 Zn zinc; 47 Ag silver; 56 Ba barium. An atom has 26 protons and 30 neutrons. Using the table, which element is it, Kira?

    • Zinc, element 30, from the neutrons
    • Copper
    • Iron
    • Barium, element 56
  7. Atomic number, symbol, name. 5 B boron; 6 C carbon; 7 N nitrogen; 8 O oxygen; 13 Al aluminum. An atom has 6 protons and 7 neutrons. Using the table, which element is it, Luz?

    • Aluminum, element 13
    • Oxygen
    • Nitrogen, from the 7 neutrons
    • Carbon
  8. Where is almost all of an atom's mass, Milo?

    • In the empty space
    • In the nucleus
    • In the electrons, since they fill the atom
    • Shared evenly among its particles
  9. Which two particles have about the same mass, Pia?

    • A neutron and an electron
    • Each of the three
    • A proton and a neutron
    • A proton and an electron
  10. a nucleus with 3 protons (marked +) and 4 neutrons (no mark), and 3 electrons (marked −) around it. Ren counts the particles in the lithium atom drawing. What is its mass number?

    • Mass number 3
    • Mass number 10
    • Mass number 4
    • Mass number 7
  11. Tala counts the particles in the beryllium atom drawing. What is its mass number?

    • Mass number 13
    • Mass number 5
    • Mass number 4
    • Mass number 9
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Protons, neutrons and electrons

Answer Key - Grade 8 Science Worksheet

Circle the best answer, or write your answer on the line.

  1. A potassium atom has atomic number 19 and mass number 39. How many neutrons does it have, Ari?

    20 neutrons
  2. A zinc atom has atomic number 30 and mass number 64. How many neutrons does it have, Bo?

    34 neutrons
  3. A silver atom has atomic number 47 and mass number 107. How many neutrons does it have, Esme?

    60 neutrons
  4. Read this first

    Table (IUPAC data)

    Atomic number, symbol, name. 6 C carbon; 7 N nitrogen; 8 O oxygen; 9 F fluorine; 13 Al aluminum; 16 S sulfur.

  5. An atom has 8 protons and 8 neutrons. Using the table, which element is it, Jun?

    • Sulfur, element 16
    • Oxygen
    • You can't tell without the electrons
    • It depends on the neutrons
  6. Atomic number, symbol, name. 26 Fe iron; 29 Cu copper; 30 Zn zinc; 47 Ag silver; 56 Ba barium. An atom has 26 protons and 30 neutrons. Using the table, which element is it, Kira?

    • Zinc, element 30, from the neutrons
    • Copper
    • Iron
    • Barium, element 56
  7. Atomic number, symbol, name. 5 B boron; 6 C carbon; 7 N nitrogen; 8 O oxygen; 13 Al aluminum. An atom has 6 protons and 7 neutrons. Using the table, which element is it, Luz?

    • Aluminum, element 13
    • Oxygen
    • Nitrogen, from the 7 neutrons
    • Carbon
  8. Where is almost all of an atom's mass, Milo?

    • In the empty space
    • In the nucleus
    • In the electrons, since they fill the atom
    • Shared evenly among its particles
  9. Which two particles have about the same mass, Pia?

    • A neutron and an electron
    • Each of the three
    • A proton and a neutron
    • A proton and an electron
  10. a nucleus with 3 protons (marked +) and 4 neutrons (no mark), and 3 electrons (marked −) around it. Ren counts the particles in the lithium atom drawing. What is its mass number?

    • Mass number 3
    • Mass number 10
    • Mass number 4
    • Mass number 7
  11. Tala counts the particles in the beryllium atom drawing. What is its mass number?

    • Mass number 13
    • Mass number 5
    • Mass number 4
    • Mass number 9