A substance undergoes change. Which Of the following indicates that the change was a chemical change?

a. the substance changed state.

b. the molecules of the substance changed

c. the substance changed shape.

d. the density of the substance changed.

How do simple machines make work easier? They increase the distance of applied forces. They change the strangth or direction of a force. o They add energy to the work. O They reduce the speed of work.

Use your Cabbage pH Indicator Key to determine the pH of each. Enter the pH ranges into the data table.

Classify each item as a pure substance or a mixture: (a) blood; (b) ocean water; (c) a piece of wood; (d) a chunk of ice.

Which of these is an ionic compound? A NO2 B LiCl C SO3 D CO

According to keplers third law what is the ratio of the squares of the periods of any two planets equal to?

Use the periodic table to determine the number of protons in an atom of arsenic (as)

Which of the following is a strong electrolyte. sugar, sodium chloride, honey vinager, carbon tetrachloride?

How do rockets work? What chemicals are used and what reactions happens with those chemicals to make a rocket fly?

The solubility of iron (ii) hydroxide, fe (oh) 2, is 1.43x10-3 gram per liter at 25oc. a. write a balanced equation for the solubility equilibrium

A substance undergoes change. Which Of the following indicates that the change was a chemical change? a. the substance changed state. b. the molecules of the substance changed c. the substance changed shape. d. the density of the substance changed.