(a) Write out the ground-state electron configuration (
) for the beryllium atom. (b) What element of nextlarger
has chemical properties similar to those of beryllium? Give the ground-state electron configuration of this element. (c) Use the procedure of part (b) to predict what element of nextlarger
than in (b) will have chemical properties similar to those of the element you found in part (b), and give its ground-state electron configuration.
The Correct Answer and Explanation is:
a) Ground-State Electron Configuration for Beryllium (Be):
The atomic number of beryllium (Be) is 4, which means it has 4 electrons. The ground-state electron configuration follows the Aufbau principle, where electrons fill the lowest energy orbitals first.
- The first two electrons will go into the 1s orbital:
1s² - The remaining two electrons will fill the 2s orbital:
2s²
Thus, the ground-state electron configuration for beryllium (Be) is:
1s² 2s²
(b) Element with Similar Chemical Properties to Beryllium:
To find an element with similar chemical properties to beryllium, we look at elements in the same group (alkaline earth metals) in the periodic table. The next element in the periodic table after beryllium (Be) is magnesium (Mg), which is in the same group (Group 2) as beryllium.
Magnesium has the atomic number 12, which means it has 12 electrons. The ground-state electron configuration for magnesium is as follows:
- The first two electrons fill the 1s orbital:
1s² - The next two electrons fill the 2s orbital:
2s² - The next six electrons fill the 2p and 3s orbitals:
2p⁶ 3s²
So, the ground-state electron configuration for magnesium (Mg) is:
1s² 2s² 2p⁶ 3s²
Magnesium shares many chemical properties with beryllium, such as the ability to form +2 cations, due to both having two valence electrons.
(c) Element with Chemical Properties Similar to Magnesium:
To predict the next element with similar properties to magnesium, we again look for the next element in the same group (alkaline earth metals). The element after magnesium (Mg) is calcium (Ca), which is in Group 2 of the periodic table.
Calcium has the atomic number 20, meaning it has 20 electrons. The ground-state electron configuration for calcium is as follows:
- The first two electrons fill the 1s orbital:
1s² - The next two electrons fill the 2s orbital:
2s² - The next six electrons fill the 2p orbital:
2p⁶ - The next two electrons fill the 3s orbital:
3s² - The next two electrons fill the 3p orbital:
3p⁶ - The next two electrons fill the 4s orbital:
4s²
Thus, the ground-state electron configuration for calcium (Ca) is:
1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
Calcium, like magnesium, shares the typical chemical behavior of alkaline earth metals, such as the formation of +2 cations.
