8th grade Protons, neutrons and electrons worksheet

Protons, neutrons and electrons

Grade 8 Science Worksheet

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

1. 1.

   A potassium atom has atomic number 19 and mass number 39. How many neutrons does it have, Ari?
2. 2.

   A zinc atom has atomic number 30 and mass number 64. How many neutrons does it have, Bo?
3. 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. 4.

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

   • It depends on the neutrons
   • Oxygen
   • Sulfur, element 16
   • You can't tell without the electrons
6. 5.

   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?

   • Iron
   • Copper
   • Zinc, element 30, from the neutrons
   • Barium, element 56
7. 6.

   Where is almost all of an atom's mass, Milo?

   • In the electrons, since they fill the atom
   • In the nucleus
   • In the empty space
   • Shared evenly among its particles
8. 7.

   How does an electron's mass compare with a proton's, Noah?

   • Exactly zero
   • About twice as much
   • Much smaller: about 1/1836 as much
   • About the same
9. 8.

   Which two particles have about the same mass, Pia?

   • A neutron and an electron
   • Each of the three
   • A proton and an electron
   • A proton and a neutron
10. 9.

    Tala counts the particles in the beryllium atom drawing. What is its mass number?

    • Mass number 13
    • Mass number 9
    • Mass number 4
    • Mass number 5
11. 10.

    Zee counts the particles in the nitrogen atom drawing. What is its mass number?

    • Mass number 21
    • Mass number 14
    • Mass number 7
    • Mass number 28