Question

Va rog sa mart ajutati mart subiectul II

Answer 1

II. M cristalohidrat = 250g

250g cristalohidrat..............160g CuSO₄...........90g H₂O
40g cristalohidrat..............x = 25,6g..................y = 14,4g

C = md/ms*100 => md = C*ms/100 = 20*1600/100 = 320g CuSO₄

ms = md+mH₂O => mH₂O = 1600-320 = 1280g

a) m H₂O total = 14,4+1280 = 1294,4g  ⇒ VH₂O = 1294,4 mL = 1,2944 L

b) 160g CuSO₄.................64g Cu
25,6g CuSO₄....................x = 10,24g

n = m/M => m =n*M = 0,1*64 = 6,4g Cu

160g CuSO₄.....................64g Cu
320g CuSO₄....................x = 128g Cu

m Cu total = 128+6,4+10,24 = 144,64g

ms final = 40+16+1600 = 1656g sol. CuSO₄

%Cu = 144,64/1656*100 = 8,73

c) m H₂O total = 1294,4g  ⇒ jumatate = 647,2g H₂O

C*mH₂O = md(100-C) ⇒ md = C*mH₂O/100-C = 20*647,2/100-20 = 161,8g H₂SO₄

ms = 647,2+161,8 = 809g sol. H₂SO₄