Write electron configurations

Answer Key - Grade 10 Science Worksheet

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

1. 1.

   An atom has a neon core of 10 electrons, 2 electrons in its outer s subshell and 1 in its outer p subshell. How many electrons does the neutral atom have, Ari?

   13 electrons
2. 2.

   An atom has a neon core of 10 electrons, 2 electrons in its outer s subshell and 3 in its outer p subshell. How many electrons does the neutral atom have, Bo?

   15 electrons
3. 3.

   An atom has a neon core of 10 electrons, 2 electrons in its outer s subshell and 5 in its outer p subshell. How many electrons does the neutral atom have, Esme?

   17 electrons

4. Read this first

   Use this

   Periodic table blocks (layout). Columns: block, groups, last subshell filled. s block, groups 1–2, s; d block, groups 3–12, d; p block, groups 13–18, p; f block, two rows below the table, f.

5. 4.

   Using the table, sodium's configuration ends in 3s¹. Which block is it in, Jun?

   • The s block
   • The p block
   • The d block
6. 5.

   Which is chlorine's noble-gas shorthand, Milo?

   • [Ne] 3s² 3p⁵
   • [He] 3s² 3p⁵
   • [Ar] 3s² 3p⁵
7. 6.

   Which is calcium's noble-gas shorthand, Noah?

   • [Ar] 3d²
   • [Ne] 4s²
   • [Ar] 4s²
8. 7.

   Which noble gas goes in the bracket for potassium's shorthand, Pia?

   • Neon
   • Krypton
   • Argon
9. 8.

   Which element is 1s² 2s² 2p⁶ 3s² 3p⁶, Ren?

   • Neon
   • Calcium
   • Argon
10. 9.

    Which is oxygen's configuration, Tala?

    • 1s² 2p⁶
    • 1s² 2s² 2p⁶
    • 1s² 2s² 2p⁴
11. 10.

    In 1s² 2s² 2p⁶ 3s² 3p³, which shell holds the outer electrons, Zee?

    • Shell 2
    • Shell 1
    • Shell 3