A student puts a tiny piece of metal into a test tube filled with water. She then puts a cap on the test tube. Which change provides evidence that a chemical reaction occurred?

A)the water bubbles
B)the mixture gets heavier
C)the water level increases
D)the metal sinks to the bottom

The diagram below shows a cell placed in a solution.a cell is shown placed inside a beaker. it is labeled cell. the solution inside the beaker is labeled 40% salt solution and the solution inside the cell is labeled 20% salt solution.only water is allowed to move in and out of the cell. what will most likely happen to the cell? it will expand as water moves out of it. it will shrink as water moves out of it.it will expand as water moves into it. it will shrink as water moves into it.

What is the molar mass of potassium nitrate, kno3

Give the set of reactants (including an alkyl halide and a nucleophile) that could be used to synthesize the following ether: draw the molecules on the canvas by choosing buttons from the tools (for bonds and charges), atoms, and templates toolbars, including charges where needed. ch3ch2och2ch2chch3 | ch3