posted by sarah on .
One kind of battery used in watches contains mercury(II) oxide. As current flows, the mercury(II) oxide is reduced to mercury.
HgO(s) + H2O( ) + 2 e– Hg( ) + 2 OH–(aq)
If 2.3 10–5 amperes flows continuously for 1200 days, what mass of Hg( ) is produced?
a. 2.5 g
b. 5.0 g
c. 9.9 g
d. 13 g
e. 15 g
coulombs = amperes x seconds.
C = 2.3E-5 x 1200 d x (24 hr/d) x (60 m/hr) x(60 s/min) = ?
96,485 coulombs will produce (200.6/2)g Hg; therefore,
g Hg = (200.6/2) x (?coulombs/96,485)