If water were a linear (not bent) molecule like co2, electrostatic interactions between water molecules would be much weaker. why?

Answer;

The partial negative charge on oxygen would stick out less and be less able to participate in hydrogen bonding.

Explanation;

Water is a polar molecule because the electrons are not shared equally, they're closer to the oxygen atom than the hydrogen.

-Normally, the water molecule is a bent shape because of the pair of lone electrons - they repulse each other and exert a compression to the hydrogen atoms at a slight 104º angle. It is a bent molecular geometry that results from tetrahedral electron pair geometry.

-The 2 lone electron pairs exerts a little extra repulsion on the two bonding hydrogen atoms to create a slight compression to a 104 degrees bond angle. Therefore, the water molecule is bent molecular geometry because the lone electron pairs.

Thus, If water were a linear molecule like co2, electrostatic interactions between water molecules would be much weaker, then the partial negative charge on oxygen would stick out less and be less able to participate in hydrogen bonding.