What is the electron configuration for Be 2+ ions?
1) 1 3) 2-1
2)2 4) 2-2
I also need an explanation for the correct and incorrect answers because I am confused by this problem.
Fill the 1s first. It can hold 2 electrons.
Fill the 2s next. It can hold 2 electrons.
Fill the 2p next (if needed). It can hold 6 electrons.
How many electrons do we need to fit into Be (the neutral atom). The atomic number is 4; therefore, Be atom is
4Be = 1s2 2s2
For the +2 ion, we remove the last two electrons. So the new configuration for the +2 ion is
1s2.
The correct answer is option 2) 2.
To determine the electron configuration of an element or ion, you need to follow a specific set of rules.
1) First, you determine the atomic number of the element. Be is the chemical symbol for beryllium, which has an atomic number of 4.
2) Next, you need to know the number of electrons in the neutral state of the element. The neutral state of beryllium has 4 electrons.
3) To represent the electron configuration, we use a notation called the "orbital notation" or the "spatial notation". This notation indicates the specific orbitals where electrons are located, and the number of electrons in each orbital.
4) The orbital notation of beryllium (Be) is 1s² 2s². This means that the first energy level (1s) has 2 electrons, and the second energy level (2s) also has 2 electrons.
Now, let's consider the Be²⁺ ion. The superscript "2+" indicates that the ion has a +2 charge, which means it has lost 2 electrons.
5) To determine the electron configuration of the Be²⁺ ion, we need to subtract 2 electrons from the neutral state of beryllium.
After losing 2 electrons, the electron configuration of Be²⁺ becomes 1s².
Looking at the options provided, option 2) 2 matches this electron configuration and is therefore the correct answer.
Now, let's analyze the other options:
1) Option 1) 1 suggests that the electron configuration of Be²⁺ is 1 electron in the 1s orbital. However, this is incorrect since beryllium in its neutral state has 2 electrons in the 1s orbital.
3) Option 3) 2-1 suggests that the electron configuration of Be²⁺ is a negative ion, which is not correct. Be²⁺ is a positively charged ion because it has lost 2 electrons.
4) Option 4) 2-2 suggests that the electron configuration of Be²⁺ is a negative ion with 2 electrons. Again, this is not correct since Be²⁺ is a positively charged ion.