Aconcept map for four types of intermolecular forces and a certain type of bond is shown.

which of the following correctly identifies the intermolecular force represented by a and compares its strength relative to the intermolecular force represented by b?

a represents london dispersion forces, which are weaker than the force represented by b.
a represents hydrogen bonding, which is weaker than the force represented by b.
a represents london dispersion forces, which are stronger than the force represented by b.
a represents hydrogen bonding, which is stronger than the force represented by b.

How has the scientific community addressed the safety of chemicals? a. chemicals are repeatedly tested, even those that have existed for a long time. b. existing chemicals are tested if they have never been tested before. c. chemicals are tested if they are suspected to have caused a problem. d. only new chemicals are tested.

The earth's moon is unusually large. two popular theories of the moon's origin include the "sister world" hypothesis, which states that the moon formed from the same materials as the earth, near enough to the earth that they fell into orbit around each other. a second theory is the "capture" hypothesis, in which the moon formed elsewhere in the solar system, and the earth's gravity pulled it into its orbit. studies of what the moon is made of indicate that some of its materials had to come from the earth or from the same area of the solar system where the earth had formed. at the same time, the moon does not contain much of the material that makes up the earth's core, so the moon could not have formed from the same materials as the earth. how do the two facts above affect the described theories of the moon's origin? a. they show that scientists will never agree on where the moon came from. b. they show that more experiments on moon formation need to be done. c. they show that no theory accounts for the existence of the moon. d. they show that neither theory is complete and entirely correct.

Which best describes why nh4+ can form an ionic bond with ci-?