№1
Оснований 3
№2
HNO3 и H2SO4, короче цифра '2'
Дано
m(C6H5OH)=4.7g
W(KOH)=10%
----------------
m(ppaKOH)-?
4.7g Xg
C6H5OH+KOH-->C6H5OK+H2O M(C6H5OH)=94 g/mol ,M(KOH)=56 g/mol
94 56
4.7/94 = X/56
X=2.8 g
m(ppaKOH)=2.8*100%/10%=28 g
ответ 28 г
N = m/M = N/Na
n(O2) = 10/32 = 0,3125 моль
N(O2) = 0,3125*6,02*10²³ = 1,89*10²³ молекул
СuSO4 + 2 NaOH = Cu(OH)2 + Na2SO4
m(CuSO4) = m раствора (CuSO4) x W (CuSO4) = 20 x 0,05 = 1г
n(CuSO4) = m / M = 1 / 160 = 0,00625 моль
n(Cu(OH)2) = n(CuSO4) = 0,00625 моль
m(Cu(OH)2) = n x M = 0,00625 x 98 =0,6125 г
200 ---100%
х --------15%
х = 30 г
AgNO3 + CaCl2 = 2AgCl + Ca(NO3)2
111 -------287
30 ---------х
<span>х = 77,6 г
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