The reactions can then be reversed with the addition of hydrochloric acid. The precipitate will reappear and then redissolve. Turn on stir plate and add NaOH solution until Al(OH)3 precipitates. Add ...

The equation shows that 1 mol of HCl reacts with 1 mol of NaOH. So the amount of NaOH in 20.0 cm 3 is 0.025 mol. Substituting into the equation to find the concentration of NaOH: \(Concentration ...

Clean the pennies in concentrated HCl. Watch zinc filled pennies (after 1983) to make sure the HCl doesn’t get to the zinc and dissolve it. Stir NaOH/Zn mixture with a glass rod. Zn will clump up on ...