What is a pure substance made of two or more elements that are chemically combined called?
element
mixture
compound
O proton

Which type of intermolecular attractions holds ammonia molecules together with other ammonia molecules?

Which substance—wood or silver—is the better thermal conductor? a thermal conductor is a material that requires very little heat energy to change its temperature. explain your answer.

In what way do investigations build scientific knowledge? the results of investigations lead to questions that cannot be tested. they reflect the opinions and social values of scientists, ensuring valid information. the results of investigations lead to new questions, which lead to new investigations. they are not influenced by the research of earlier scientists, so they are able to address gaps in understanding.i