<span>37,5/12 : 12,5/1 = 3,125 : 12,5 = 1 : 4 </span>
<span>СН3ОН метанол </span>
<span>СН3ОН + RCOOH = CH3-O-CO-R </span>
<span>М = 37 х 2 = 74 </span>
<span>74 = М( CH3-O-CO) + М(R) </span>
<span>М(R) =74 - 59 =15</span>
.................................................................
CH≡CH + NaNH2 -> CH≡CNa + NH3
1) Zn, NaOH, BaCl2, K2CO3.
FeSO4 + Zn = ZnSO4 + Fe
FeSO4 + 2NaOH = Fe(OH)2↓ + Na2SO4
FeSO4 + BaCl2 = BaSO4↓ + FeCl2
FeSO4 + K2CO3 = FeCO3↓ + K2SO4
2) Fe, AgNO3, K2S, NaOH, K3PO4.
CuCl2 + Fe = FeCl2 + Cu
CuCl2 + 2AgNO3 = 2AgCl↓ + Cu(NO3)2
CuCl2 + K2S = CuS↓ + 2KCl
CuCl2 + 2NaOH = 2NaCl + Cu(OH)2↓
3CuCl2 + 2K3PO4 = Cu3(PO4)2↓ + 6KCl
3) HNO3, CaCl2, H2SO4, FeCl2.
Na2CO3 + 2HNO3 = 2NaNO3 + H2O + CO2↑
Na2CO3 + H2SO4 = Na2SO4 + H2O + CO2↑
Na2CO3 + FeCl2 = 2NaCl + FeCO3↓
4) AgNO3, CuCl2, H2SO4.
K2S + 2AgNO3 = Ag2S↓ + 2KNO3
K2S + CuCl2 = CuS↓ + 2KCl
<span>K2S + 3H2SO4 → 2KHSO4 + SO2</span>↑<span> + S + 2H2O</span>
M р-ра=75+10=85 г
w=m в-ва/m р-ра*100\%=10/85*100\%=11.8\%
n=m/M=10/342=0.03 моль сахара C12H22O11
Mr(C12H22O11)=144+22+176=342
<span>N=6*10^23*n=6*10^23*0.03=0.18*10^23=18*10^21 молекул сахара</span>