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Complete the following reactions using word and balanced equations including states. dilute phosphoric acid is added with a calcium hydroxide solution.

Significant figures are digits read directly from the measuring instrument plus one more digit, which is __ by the observer.

In the cathode ray tube experiment, j. j. thomson passed an electric current through different gases inside a cathode ray tube in the presence of an electric field. in which two ways did this experiment change scientists’ understanding of the atom?