What is the percent composition of hydrogen in nh4hco3?

Match the formula for the following compound:   magnesium sulfate heptahydratemgs·7h2omg2so4·7h2omg(s o4)2·7h2omgso4·7h2o

What is the solution to the problem to the correct number of significant figures (102,900/12)+(170•1.27)

If the standard reduction potential of a half-cell is positive, which redox reaction is spontaneous when paired with a hydrogen electrode? reduction both reduction and oxidation neither reduction nor oxidation oxidation