Question

question 4 (1 point) using the vsepr theory, predict that the shape of beryllium dihydride, beh₂. bent linear regular tetrahedral triangular planar trigonal pyramidal question 5 (1 point) which of the following correctly describes the shape of a molecule of sic₄? tetrahedral trigonal pyramidal bent trigonal bipyramidal

Explanation:

Step1: Determine the central - atom and valence - electron pairs for BeH₂

Beryllium (Be) is the central atom. Be has 2 valence electrons and each H contributes 1 electron. So, the total number of valence - electron pairs around Be is $\frac{2 + 2}{2}=2$ bonding pairs and 0 lone pairs. According to VSEPR theory, a molecule with 2 bonding pairs and 0 lone pairs has a linear shape.

Step2: Determine the central - atom and valence - electron pairs for SiCl₄

Silicon (Si) is the central atom. Si has 4 valence electrons and each Cl contributes 1 electron. So, the total number of valence - electron pairs around Si is $\frac{4+4}{2} = 4$ bonding pairs and 0 lone pairs. According to VSEPR theory, a molecule with 4 bonding pairs and 0 lone pairs has a tetrahedral shape.

Answer:

Question 4: B. linear
Question 5: A. tetrahedral