Molecules with large dipole moments are likely to:?

Question

A. have lower melting points than molecules with no dipole moments
B. have higher boiling points than molecules with no dipole moments
C. exist as gases
D. have their physical properties strongly influenced by London forces

Answer 1

B

Answer 2

The answer is B. Molecules with large dipole moments have dipole-dipole interactions between them that cause the molecules to be strongly attracted to each other. Molecules with no dipole moment will only experience London forces, which in general are substantially weaker than dipole-dipole interactions. The greater the attractive forces between molecules, the higher the boiling point will be.

Answer 3

Indeed, you have asked the multi-trillion dollar question. Lots of people are arguing over that issue right now. The fact is that CO2 has, by itself, only a very tiny effect. The major greenhouse gas is water vapor. CO2 is about 1000x less effective than water vapor as a greenhouse gas. That would be the end of it, but for the issue of feedback. Those who accept the anthropogenic global warming hypothesis believe that the greenhouse effect of the CO2 triggers a larger greenhouse effect that involves water vapor. The climate models that predict global warming are programmed with an assumed value for this feedback. The warmists think it is large, and us skeptics think it's not. Some of us think it is not only small, but negative. This feedback effect is usually described in terms of climate sensitivity, or how many degrees C will the climate warm for a doubling of the CO2 concentrations. The camps seem to divide at about 2°C; those who think the sensitivity is greater than 2°C for doubling the CO2 tend to be warmists, and those of us who think the sensitivity is less than 2°C tend to be the skeptics. The IPCC relies on climate models that show a sensitivity ranging from 2°C to 4.5°C, with a 'best estimate of 3°C. Lindzen and Choi published a paper in 2009 that analyzed satellite measurements of energy radiated to space, and found their data indicated that the energy radiated to space increases with ocean temperature, while all the models predict it will decrease as ocean temperature increases. This is related to the sensitivity. Lindzen and Choi report their estimate of climate sensitivity to be 0.5°C. If this is correct, the feedback effects are too small to worry about and the whole global warming thing is a big non-event. The sensitivity is also a big issue with regards to policy-making regarding carbon emissions. If the sensitivity is low, it is so in both directions, up and down. Thus, low sensitivity means that the climate will no be affected much by limiting carbon emissions: huge reduction in emissions will have very small, even imperceptible, effects on global temperatures. Carlin (2011) thinks the sensitivity is low, and as a result the *cost* of reducing temperatures by controlling carbon will be much higher than everybody thinks, and much to high to be reasonable. I think Lindzen, Choi, and Carlin are right. Someone else is likely to tell you they are not. Time, ultimately, will tell.