Answer:
The shape of the BF3 molecule is best described as trigonal planar.
Explanation:
The Lewis Structure for BF3 is like this:
_ _
| F | | F |
\ /
B
|
| F |
---
It forms three angles of 120° each. The bonds are in the same planar that's why it is trigonal planar and they are exactly the same.
Boron and Fluorine have 3 covalent bonds, produced by electronic promotion that enables the 2py and 2pz orbitals, leaving an electron to pair in the 2px. So boron will have 3 possible electrons to pair in 2s1, 2px and 2py, remember that electronic configuration for B is 1s2, 2s2, 2p1
By hybridization between the orbitals 2s2 and 2p1, the electrons of F, can joined to make the covalent bond. The new B configuration is 1s2, 2s1, 2px1, 2py1 (these last three, hybrid orbitals)
I think the correct answer from the choices listed above is option B. <span>Of its 6 electrons, 4 are valence electrons, a carbon atom can form 4 covalent bonds with other elements. It is the 4 valence electrons available that allows this.
Hope this answers the question.</span>
The atomic radius increases as we go down a group/family on a periodic table.
Explanation:
"Atomic radius" is defined as the "one-half of the distance" between the "nuclei of two atoms". While moving down the group in a periodic table there is an "increase in quantum number n" which allows the valence electrons to occupy on higher levels. This shows that the valence electrons move away from the nucleus, which makes them to be loosely held. Thus, atomic radius is large.
Similarly while moving across the periodic table from "left to right" the atomic radius gradually decreases.
Cars still largely rely on oil so the answer is b