Refer to a radioactive isotope for which t1/2 = 224.8 min. How long will it take a 12.6 g sample to decay to 5.5 g?

Given the following half-reactions, which are arranged in the same order as in Table 3 (voltages become more positive from top to bottom): Pb2+ + 2 e-

Suppose a radioactive isotope has a half-life t1/2 = 62.5 min. How long will it take for a sample to decay to 15% of its original activity?

Consider the overall reaction: 2NO + H2

For the following correctly balanced redox reaction: MnO2(s) + Cu(s) + 4H+

If Eocell for a redox reaction is negative, which of the following statement(s) must be true?  1.

he isotope decays to  .  What decay process has occurred?

Hydrocyanic acid, HCN, dissociates as follows: HCN(aq) ⇌ H+(aq) + CN- (aq).The Ka (which is also the Keq) is 4.9 x 10-10 at 298 K. Use the Ka (Keq) value to calculate

Which is the correct equation for  decaying by electron capture?

Which of the following reactions is expected to have a positive