Which option correctly describes the following features of a silane (silicon tetrahydride) molecule?
number of bonding pairs (bp) of electrons
number of lone/non-bonding pairs (lp) in the valence shell of the silicon atom
bond angle
[Atomic number: Si = 14; H = 1]
A. 3 bp; 1 lp; 107°
B. 3 bp; 1 lp; 109.5°
C. 4 bp; 0 lp; 109.5°
D. 4 bp; 2 lp; 90°
E. 4 bp; 0 lp; 90°
The correct answer is option C: “4 bp; 0 lp; 109.5°”. This is because the silicon atom forms four bonds with the hydrogen atoms, and there are no lone pairs of electrons in the valence shell of the silicon atom. The bond angle is 109.5 degrees because that is the typical bond angle for a tetrahedral molecule.
To find the number of valence electrons in a silicon tetrahydride molecule, you can follow these steps:
First, you need to know the atomic number of each element in the molecule. The atomic number is like a fingerprint for each element and it tells us how many protons are in the nucleus of an atom. For silicon, the atomic number is 14, and for hydrogen, the atomic number is 1.
Next, you can use the periodic table to find the number of valence electrons for each element. The periodic table is a chart that shows us the different elements and their properties. Valence electrons are the electrons that are in the outermost energy level of an atom, and they help us understand how atoms will bond with each other. To find the number of valence electrons for an element, you can look at the periodic table and find the highest energy level for that element. For silicon, there are four valence electrons, and for hydrogen, there is one valence electron.
Finally, you can add up the number of valence electrons for each element to find the total number of valence electrons in the molecule. In a silicon tetrahydride molecule, there are four valence electrons from the silicon atom and four valence electrons from the hydrogen atoms, for a total of eight valence electrons.