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Asample of radium-226 will decay 1/4 of its original amount after 3200years. what is the half-life of radium-226?

You encounter a solution that is acidic and you decide to test it by adding a small amount of a strong acid. the ph lowers slightly but is approximately unchanged, and still remains acidic. what can you say about the solution? a. it is a buffer solution. b. it is not a buffer solution it is a strong acid solution. d. the solution has been neutralized. e. the solution has excess acid present

The number at the end of an isotope’s name is the number.