In a lever, the fulcrum isn't always between the load and the effort. In your own words, describe how this changes the usefulness of the lever.

This chart represents the melting point of several substance. what besy explains the high melting point of the salt?

An atom of which element reacts with an atom of hydrogen to form a bond with the greatest degree of polarity ?

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.