Question

(02.03 mc) sulfur (s) has an atomic number of 16. what is the electron configuration of sulfur?
o a 1s²1p⁶2s²2p⁶
o b 1s²2s²2p⁶3s²3p⁴
o c 1s²2s²2p⁶2d⁶
o d 1s²1p⁶1d⁷
pregunta 5 (3 puntos)
(02.03 mc)
which of the following is a reasonable electron configuration?
o a 1s²2s²2p⁶3s²
o b 1s²2s²2p⁶3s²3d⁴
o c 1s²2s²2d¹⁰2p³
o d 1s²2s²2p³2d⁶

Explanation:

For the first question about sulfur (atomic number 16), electrons fill orbitals in the order 1s, 2s, 2p, 3s, 3p etc. with s - orbitals holding 2 electrons, p - orbitals holding 6 electrons. The electron - configuration for sulfur is 1s²2s²2p⁶3s²3p⁴. For the second question, in a correct electron - configuration, electrons fill lower energy orbitals first. The 2d orbitals do not exist (the first d - orbitals start at n = 3), so options with 2d are incorrect. Option a (1s²2s²2p⁶3s²) is a valid electron - configuration for magnesium (atomic number 12).

Answer:

1. B. 1s²2s²2p⁶3s²3p⁴
2. A. 1s²2s²2p⁶3s²