К 0.5 литрах раствора серной кмслоты с массовой долей 98% и плотностью 1.887 г/мл прибавлено 3 литра воды. Какова массовая доля серной кислоты в полученном растворе?​

W=m(в-ва)\m(р-ра)
1. M(HBr) = 1+80 = 81
w(H) = 1\81 = 0.01253*100% = 1.23%
w(Br) =  100%-1.23% = 98.77%
2. M(K₂CO₃) = 2*40+16*3+12 = 140
w(K₂) = 80\140 = 0.57*100%= 57%
w(C) = 12\140 = 0.086*100% = 8.6%
w(O₃) = 100%-57%-8.6% = 34.4%
3. M(Mg(OH)₂) = 24+16*2+1*2 = 58
w(Mg) = 24\58 = 0.414*100% = 41.4%
w(O) = 32\58 = 0.552*100% = 55.2%0
w(H) = 100%-41.4%-52.2% = 6.4%
4. M(P₂O₅) = 31*2+16*5 = 142
w(P₂) = 62\142 = 0.423*100% = 42.3%
w(O₅) = 100%-42.3% = 57.7%
5. M(FeCl₃) = 56+35.5*3 = 162.5
w(Fe) = 56\162,5 = 0.345*100% = 34.5%
w(Cl₃) = 100%-34.5% = 65.5%
6. M(Cu(NO₃)₂) = 64+28+96 = 188
w(Cu) = 64\188 = 0.34*100% = 34%
w(N) = 28\188 = 0.15*100% = 15%
w(O₃) = 100%-34%-15% = 51%

1)Mr(HBr) = Ar(H) + Ar(Br) = 1 + 80 = 81

w (H/HBr) = Ar(H)/ Mr(HBr) x 100%  = 1/81 х 100 = 1,23%

w (Br/HBr) = Ar(Br)/ Mr(HBr) x 100%  = 80/81 х 100 = 98,77%

2) Mr(K2CO3) = 2Ar(K) + Ar(C) + 3Ar(O) = 2x39 + 12 + 3x16 = 138

 w (2K/K2CO3) = 2Ar(K)/ Mr(K2CO3) x 100%  = 78/138 х 100 = 56,52%

 w (C/K2CO3) = Ar(C)/ Mr(K2CO3) x 100%  = 12/138 х 100 = 8,69%

 w (3О/ K2CO3) = 3Ar(О)/ Mr(K2CO3) x 100%  = 48/138 х 100= 34,79%

3)Mr(Mg(OH)2) = 24 + 16x2 + 1x2 = 58

w (Mg/Mg(OH)2) = 24/ 58 х 100 = 41,38%

w (2O/Mg(OH)2) = 32/ 58 х 100 = 55,17%

w (2H/Mg(OH)2) = 2/ 58 х 100 = 3,45%

4)Mr(P2O5) = 2x31 + 5x16 = 142

w (2P/P2O5) = 2x31/ 142 х 100 = 43,66%

 w (5O/P2O5) = 5x16/ 142 х 100 = 56,34% 5)Mr(feCl3) = 56 + 3 x 35,5 = 162,5  w (Fe/FeCl3) = 56/ 162,5 х 100 = 34,46%  w (3Cl/FeCl3) = 3x35,5/ 162,5 х 100 = 65,54% 6)Mr(Cu(NO3)2) = 64 + 2x14 + 6x16 = 188 w (Cu/Cu(NO3)2) = 64/ 188 х 100 = 34,04%  w (2N/ Cu(NO3)2) = 2x14/ 188 х 100 = 14,9% w (6O/Cu(NO3)2) = 96/ 188 х 100 = 51,06%