Question

trung hoa 300 gam dung dich ca(OH)2 18,5% can dung vua du 200 gam dung dich axit hcl thu duoc dung dich A.

b)tinh khoi luong muoi thu duoc trong dung dich A ?

c)Tinh nong do phan tram cua muoi trong dung dich A?

MONG CAC BAN CAC THAY CO GIUP EM !"^_^"

 

 

Answer 1

mCa(OH)2=55(g)

nCa(OH)2=0.75(mol)

Ca(OH)2+2HCl->CaCl2+2H2O

nCaCl2=nCa(OH)2=0.75(mol)

mCaCl2=83.25(g)

 

C% muối:83.25:500*100=16.65%

Answer 2

b/ m _Ca(OH)2= 300 . 18,5% = 55,5 gam

    n_Ca(OH)2 = 55,5 : 74 \(\approx0,75\left(mol\right)\)

PTHH Ca(OH)2 + 2HCl ---> CaCl2 + 2H2O

           0,75 mol-----------------0,75mol

=> m_CaCl2= 0,75 x 111 = 83,25 gam

c/ Ta có : mdd sau pứ = mdd Ca(OH)2 + mdd HCl = 300 + 200 = 500 gam

=> C%_Ca(OH)2= 83,25 / 500 x 100% = 16,65%

 Vậy ..........