The flame goes an Orange-Red colour.
The traditional calcium atom has twenty protons and twenty electrons making it neutral.
The calcium in the pic is a calcium ion so the number of protons and electrons are not equivalent.
Since it's 2+ that means the ion is positively charged and for that to happen electrons are away.
So 20-2=18
There are 18 electrons
The electron group arrangement of PH₃ is tetrahedral. The molecular shape is a Trigonal pyramid, and the bond angle is 93°.
<h3>What is the bond angle?</h3>
The angle between the atoms in a compound is known as the bond angle. The degree of the binding angle is specified. There is also the bond length. It is the separation between the two atoms' nuclei.
The bond angle between the atoms of phosphine is 93°. It has one lone pair. The central atom is covered with 4 atoms.
Thus, the electron-group arrangement of phosphine is tetrahedral. The molecular geometry or shape is a trigonal pyramid. The bond angle is 93°.
To learn more about bond angles, refer to the link:
brainly.com/question/1851495
#SPJ4
Here are the resonance contributors I found.
