Question

answer the questions about the following model
there are 1 reds (regions of electron density) around the central atom
a. 0 b. 1 c. 2. d. 3 e. 4
the shape at the central atom is 2
f. diatomic g. linear h. trigonal planar i. bent (120°)
j. tetrahedral k. pyramidal l. bent (109.5°)
if all of the bonds are polar covalent, is the molecule itself polar ? 3
m. yes n. no

Explanation:

Step1: Count regions of electron density

Count the number of bonds and lone pairs around the central atom. In the model, there are 4 bonds (no lone pairs), so 4 REDs.

Step2: Determine molecular shape

For 4 REDs (all bonds, no lone pairs), the shape is tetrahedral.

Step3: Check polarity

If all bonds are polar covalent and the molecule is tetrahedral (symmetrical in this case, assuming all attached groups are the same in terms of electronegativity - which is implied as we are just going by the shape and bond type as given), the dipoles cancel out. But wait, no - wait, hold on. Wait, no - if it's a tetrahedral with 4 identical bonds (which is what the model seems to show - 4 bonds from central atom to same - colored atoms), but wait, no - tetrahedral shape. Wait, no - actually, if all 4 regions are bonds (assuming they are to the same atom), but in reality, for polarity: if a molecule is symmetrical (like a regular tetrahedral with all same - bonded atoms), the dipoles cancel. But wait, no - wait, in VSEPR, for example, in \(CH_4\) (tetrahedral), \(C - H\) bonds are polar, but the molecule is non - polar.

Answer:

1. E. 4
2. J. tetrahedral
3. N. no