Question

gizmo warm - up just like passengers getting on a bus, electrons orbit the nuclei of atoms in patterns (and how electrons sometimes act like passengers boarding a bus) with the electron configuration gizmo. to begin, check that lithium is selected on the periodic table tab. 1. the atomic number is equal to the number of protons in an atom. how many protons are in a lithium atom? 2. a neutral atom has the same number of electrons and protons. how many electrons are in a neutral lithium atom? 3. select the electron configuration tab, and check that energy is selected. click twice in the 1s box at lower left and once in the 2s box. observe the atom model at right. a. what do you see? b. click check. is this electron configuration correct?

Explanation:

Step1: Recall atomic - number property

The atomic number of an element is equal to the number of protons in its atom. Lithium has an atomic number of 3. So, the number of protons in a lithium atom is 3.

Step2: Use neutral - atom property

In a neutral atom, the number of electrons is equal to the number of protons. Since a lithium atom has 3 protons, a neutral lithium atom has 3 electrons.

Step3: Understand electron - configuration filling

The 1s orbital can hold a maximum of 2 electrons. When we click twice in the 1s box in the electron - configuration tool for lithium:

A. Observation

We see 2 electrons in the 1s box.

B. Electron - configuration check

The electron - configuration of lithium is 1s²2s¹. After filling 2 electrons in the 1s box, the electron - configuration shown is partially correct as the 1s part is filled correctly, but we still need to account for the remaining 1 electron in the 2s orbital.

Answer:

1. 3
2. 3
3. A. 2 electrons in the 1s box

B. Partially correct