For the indicated atom in each of the following molecules or ions, give the number and arrangement of the electron pairs around that atom.
(a) As in AsO43-
number:
arrangement:
linear
bent
trigonal planar
square planar
tetrahedral
(b) Se in SeO42-
number:
arrangement:
linear
bent
trigonal planar
square planar
tetrahedral
(c) S in H2S
number:
arrangement:
linear
bent
trigonal planar
square planar
tetrahedral
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could u check if im right:
a. As in AsO43-
for number its 3
arrangement is tetrahedral
b. Se in SeO42-
# is 2
arrangement is tetrahedral
c. S in H2S
# is 1
arrangement is linear
(a) For As in AsO43-, the number of electron pairs around As is 4. The arrangement of electron pairs around As is tetrahedral.
(b) For Se in SeO42-, the number of electron pairs around Se is 4. The arrangement of electron pairs around Se is tetrahedral.
(c) For S in H2S, the number of electron pairs around S is 2. The arrangement of electron pairs around S is bent.
To determine the number and arrangement of electron pairs around a central atom, we need to follow a few steps:
Step 1: Identify the central atom.
Step 2: Determine the molecular geometry based on the number of electron pairs around the central atom.
Step 3: Determine the arrangement of the electron pairs (bonding and non-bonding) based on the molecular geometry.
Let's go through each of the given molecules or ions:
(a) As in AsO43-
Step 1: The central atom in AsO43- is As.
Step 2: The molecular geometry is tetrahedral since there are four electron pairs around the central atom.
Step 3: The arrangement of the electron pairs is tetrahedral.
Therefore, the number of electron pairs is 4, and the arrangement is tetrahedral.
(b) Se in SeO42-
Step 1: The central atom in SeO42- is Se.
Step 2: The molecular geometry is tetrahedral, as there are four electron pairs around the central atom.
Step 3: The arrangement of the electron pairs is tetrahedral.
Thus, the number of electron pairs is 4, and the arrangement is tetrahedral.
(c) S in H2S
Step 1: The central atom in H2S is S.
Step 2: The molecular geometry is bent, as there are two electron pairs around the central atom.
Step 3: The arrangement of the electron pairs is bent.
Hence, the number of electron pairs is 2, and the arrangement is bent.