Predict the bond angles in each of the following molecules:

^+^CH3 and Cl4Si

My first guesses for 120 and 109.5 degrees, but not too sure

I agree with 120 for the first and 109.5 for the second.

thanx bae

To predict the bond angles in each of the following molecules, ^+^CH3 and Cl4Si, we need to consider their molecular geometries.

1. ^+^CH3 (methyl cation):
The methyl cation (^+^CH3) consists of one carbon atom with three hydrogen atoms attached. Since there is no lone pair on carbon and the molecule has a trigonal planar shape, the bond angles are expected to be around 120 degrees. So, your initial guess of 120 degrees is correct.

2. Cl4Si (tetra-chloro silane):
Cl4Si consists of a silicon (Si) atom bonded to four chlorine (Cl) atoms. The central Si atom has four bonding pairs and no lone pairs of electrons. In a tetrahedral arrangement, the bond angles are expected to be around 109.5 degrees (ideal tetrahedral angle). Your initial guess of 109.5 degrees is correct.

So, your guesses of 120 degrees for ^+^CH3 and 109.5 degrees for Cl4Si are both accurate.

To predict the bond angles in molecules, it is necessary to understand their molecular geometry. Let's analyze the two given molecules:

1. ^+^CH3 (also known as methyl cation):
The molecular geometry around the carbon atom can be determined by looking at the number of electron groups around it. In this case, there are four electron groups: three hydrogen atoms and one lone pair. The molecular geometry is tetrahedral.

In a tetrahedral geometry, the bond angles are all identical and measure approximately 109.5 degrees. Therefore, the bond angles in ^+^CH3 are expected to be around 109.5 degrees.

2. Cl4Si (tetrachlorosilane):
Similar to the previous molecule, we need to assess the molecular geometry by considering the electron groups around the silicon atom. In Cl4Si, the silicon atom is bonded to four chlorine atoms, resulting in a tetrahedral electron geometry.

However, as opposed to ^+^CH3, there are no lone pairs around the central silicon atom in Cl4Si. Thus, there are only bond angles to consider, which are all the same in a tetrahedral geometry. The bond angles are expected to be approximately 109.5 degrees.

So, both molecules are expected to have bond angles around 109.5 degrees.