Dau coroana
Am nevoie urgent de rezolvare
Va rog!!!!!

ms.HNO3 = 20 g, c% = 21%
stim ca c% = mdx100/ms
=> md = msxc%/100
= 20x21/100 = 4,2 g HNO3
md g 4,2 g
NaOH + HNO3 --> NaNO3 + H2O
40 63
=> md = 40x4,2/63 = 2,67 g NaOH
din c% => ms = mdx100/ms
= 2,67x100/20 = 13,33 g sol NaOH