1L = 1000 cm^3
500 cm^3 = 0,5L
700g H2SO4.......................1L
x = 350g H2SO4..............0,5L
MH2O = 18g/mol
n = m/M => m =n×M = 50×18 = 900g H2O
ms = m acid + m H2O = 350+900 = 1250g
a) ro = m/V = 350/500= 0,7g/cm^3
b) Cf = md/ms×100 = 350/1250×100 = 28℅
c) roH2O = 1g/cm^3
V H2O = 900cm^3
Vsf = 500 + 900 = 1400
ro = ms/V = 1250/1400 = 0,892g/cm^3