To come up with the electron configuration for Arsenic, you first need to count up how many electrons it has (it will be the same as the atomic number since the charge is neutral)... 18. Then you need to follow the aufbui order and work your way up the orbitals filling them in. 1s takes 2electrons, 2s takes 2 electrons, 2p takes 6 electrons, 3s takes 2 electrons, and lastly 3p takes 6 electrons (total of 18). The order of the orbitals and how many electrons each can take you will just need to memorize or learn some tricks to remember.
You can also just take a short cut and ignore all the orbitals before the row Arsenic is on to show ONLY the valence electrons, ie:
[Ne] 3s2 3p6
If you are still having trouble, http://mymcat.com/wiki/Electron_Configuration, has a lot of examples, including your question.
A metalloid in the ground state typically has an electron configuration that exhibits characteristics of both metals and nonmetals. For example, arsenic (a metalloid) has an electron configuration of [Ar] 3d10 4s2 4p3 in its ground state. The varying valence electron shells contribute to the unique properties of metalloids.
The electron configuration of 1s22s22p3s1 is not the ground state electron configuration of any element. This configuration contains 8 electrons, which in the ground state would be oxygen. The ground state configuration of oxygen is 1s22s22p4.
The ground state electron configuration of bromine is Ar 4s 3d 4p.
The ground-state electron configuration for the V3 ion is Ar 3d2.
The ground state electron configuration for iron (Fe) is Ar 3d6 4s2.
A metalloid in the ground state typically has an electron configuration that exhibits characteristics of both metals and nonmetals. For example, arsenic (a metalloid) has an electron configuration of [Ar] 3d10 4s2 4p3 in its ground state. The varying valence electron shells contribute to the unique properties of metalloids.
The electron configuration of 1s22s22p3s1 is not the ground state electron configuration of any element. This configuration contains 8 electrons, which in the ground state would be oxygen. The ground state configuration of oxygen is 1s22s22p4.
The ground state electron configuration of bromine is Ar 4s 3d 4p.
The ground-state electron configuration for the V3 ion is Ar 3d2.
The ground state electron configuration for nitrogen is [He]2s2.2p3.
The ground state electron configuration for iron (Fe) is Ar 3d6 4s2.
The ground state electron configuration of iron (Fe) is Ar 3d6 4s2.
Arsenic is paramagnetic because the electron configuration is {Ar}4s^2,3d^10,4p^3. Due to the unpaired electron at the end (4p^*3*) the atom in ground state is paramagnetic. **OR Arsenic would be paramagnetic since the 4 p orbitals each contain one electron with parallel spin. These three unpaired electrons give arsenic its paramagnetic property.
Ground state electron configuration of zinc (Zn): [Ar]3d104s2.
The ground state electron configuration of Lanthanum is [Xe] 5d1 6s2.
The expected ground-state electron configuration of copper is ; however, the actual configuration is because a full dsubshell is particularly stable. There are 18 other anomalous elements for which the actual electron configuration is not what would be expected.
The electron configuration of a vanadium atom in its ground state in the V3 oxidation state is Ar 3d2.