What are some examples of a physical change? (list more than 2 examples)

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

What is a number added in front of a formula in order to balance the equation

What conclusion can you draw from this experiment about the components of the black ink?