CaBr2 is mainly used in high concentration of water solution for drilling purpose or as ingredient of food preservative or for prepare freezing mixture.
Calcium Bromide is a white powder with crystalline texture and having other properties. We can explain these properties with the help of the CaBr2 lewis structure and the behavior of the outer orbit electrons which are shown in the structure.
How to draw Cabr2 lewis structure?
CaBr2 lewis structure is a presentation way for showing the bonding pattern between the atoms with the loosely bonded outer shell electrons. Calcium is in group 2 in the Periodic table with the electronic arrangement, [Ar] 4s2.
Bromine is a non-metal element with the arrangement of electrons, [Ar] 4s2 3d10 4p5. So the molecule contains total sixteen loosely attached electrons around the particular nucleus. Having less capability to pull the electron cloud, Calcium becomes central atom.
Bromine atoms remain to the opposite sides of Calcium atom and transferring electron cloud form ionic bonds. The sigma bond between the Calcium and Bromine atom is shown by a single line in the CaBr2 lewis structure and the ions are written inside bracket.
Cabr2 lewis structure resonance
Resonance is a concept of VBT where the electron cloud can delocalize to the neighbor vacant orbital and form a canonical structure which contributes in the main structure of the molecule.
In an ionic molecule like CaBr2 where the electron cloud is fully transferred to the nonmetal atom vacant shell, there is no chance to delocalize the electron cloud again to form resonating structure.
Cabr2 lewis structure shape
Molecular geometry and shape are two slightly different things where which we can clearly understand by the hybridization of central atom of a covalent molecule. Lone pair distorted the geometry by steric repulsion and introduces the molecular shape.
As an ionic compound the oppositely charged ions bounded by strong force in the lattice structure. So individually we can’t define the shape of the ionic molecule by hybridization method. Small unit of molecule repeatedly arranged to form the lattice structure.
But it can be said that the molecule has two ionic where Calcium atom is in the central position.
Cabr2 lewis structure formal charge
In the assumptions of the formal charge calculation of particular atom of a molecule, it is stated that bonding electron cloud must be distributed equally over the two atoms which only possible in the case of molecular orbital overlapping.
In CaBr2 lewis structure electron cloud is fully transferred so two oppositely charged ions, i.e, Cation and Anion produced. So here we count the oxidation number in state of the formal charge, where oxidation number is the charge gained by an atom during electron transfer.
Calcium losses its two electrons, so electronic charge decreases in the atom, results in a positively charged ion formation with charge (+2), which means oxidation number of Calcium atom in the CaBr2 lewis structure is (+2).
We can calculate the oxidation number of Bromine atom in the CaBr2 lewis structure by the same process which will be (-1). Hence overall the molecule CaBr2 is electronically nutral.
Cabr2 lewis structure angle
Bond angle is a parameter of a molecular structure which is covalent in nature. This covalent type of bonding is formed by hybrid orbital overlapping, so mainly electron cloud is shared between the adjacent atoms, which are not possible in ionic compound.
In ionic compound the oppositely charged particles tightly packed by strong attracting force and arranged in a particular geometric way to produce lattice. So no such angle is measured in this type of ionic compound.
Cabr2 lewis structure octet rule
Eight electrons are arranged in the orbit which is wave functions of specific energy in such a way that the molecule gets stabilization energy. This termed as Octet rule. Nobel gases have this type of energetic stability.
Calcium have two extra electron in 4s orbital than its nearest inert gas Argon. These are transferred to two Bromine atoms which lack one electron to gain this stability. By this method both atoms bring stability in CaBr2 lewis structure.
Cabr2 lewis structure lone pairs
After molecular formation some atom contains such valence electron pair which only spread over that atom and don’t take part in the bond formation, are known as lone pair electron. These electron cloud concentration is higher than bonding electron.
Lone pair electron has negative character so can posses in a particular vector direction. In CaBr2 lewis structure two electrons of outer shell 4s orbital of Ca are fully transfer to vacant 4p orbital of Br and it become ion with positive charge so there is no lone pair over Ca atom.
As lone pair electron cloud spread over more space with higher charge density, it can disturb the bond angle as well as the shape of the molecule.
Cabr2 valence electrons
The last shell containing electrons which are energetically approachable for excitation in any chemical reaction are known as valence electrons. This are far apart from the nucleus and for the shielding of inner orbital electrons, are loosely bounded.
Being a group 2 element in 4th Period, Calcium has two loosely bounded electrons in 4s orbital whereas Bromine contains seven that type of electrons in 4s and 4p orbitals. So total sixteen electrons loosely bounded by the nuclear force are present in the molecule.
Among these valence electrons two pairs are joined in the two Ca-Br bonding. Other remains equally distributed over two Br atoms as non-bonding electron pairs.
Hybridization is the concept for covalent compounds where energetically equal but not equivalent atomic orbitals intermixes to form equivalent orbital so that molecular orbital can form by greater atomic hybrid orbital overlapping.
Calcium Bromide is ionic compound where the atoms are connected by totally transfer of electrons from metal atom, Calcium 4s orbital to the halogen, Bromine atom p orbital. Hence here is no requirement for formation of any hybrid orbital for bonding generation.
Solubility in water depends on the fact that if the solute contains any polar part in it as water itself is a polar molecule. Being an ionic compound CaBr2 can attract water molecules and form hydrated structure generally with six water molecules.
It also can soluble in acetone solution.
Is Cabr2 acidic or basic?
If we notice the formation of the CaBr2 lewis structure, we see that it forms by the chemical nutralization reaction between a strong acid (high capability of accepting electron) and strong base.
Hence CaBr2 is nor acidic or basic, rather it is a neutral salt.
Is cabr2 ionic?
If atoms of a molecule are bonded together by electrostatic force, then it is ionic compound means it consists of oppositely charged particles which are tied up with the force. Generally metal and nonmetal form cation and anion respectively to produce this with high melting point.
Calcium is an alkali earth metal categorized in group 2 and Bromine is a non-metal element (halogen) which located in group 17. Following the Octet rule to cover the last filled shell, permanent electron transfer occurs from Ca to Br (not share). Opposite charges packed together.
After forming the ionic bonding the energy of the molecule stabilizes very much, difficult to separate ions as strong Coulombic force is acted between them. Also the charge on cation is (+2), making ions closely packed, results in high melting point of CaBr2 lewis structure around 730 ̊ C.
As a whole we can say for being ionic compound CaBr2 lewis structure form lattice structure and shows different characteristics.