In the series, the serf tells the story of the life of an eighteen-year-old girl Catherine. From birth, she was a serf but was brought up as a real court lady. Katerina was educated, but the most important thing for Katya was not freedom. Once in the life of Katya, a beautiful nobleman Alexei appears. At first glance, she fell in love with him. But unfortunately Alexey died. After that, Katerina started having problems. In this series two worlds are shown. The poor and the rich. This is a melodrama In which the main characters Katya Kovalchuk, Alexei Yarovenko, Olga Sumskaya, Mark Drobot, Olesya Zhurakovskaya, Stanislav Boklan. The director of the melodrama is Felix Gerchikov. This is a very interesting series for both teenagers and adults, very mesmerizing and impressive!
Отв. 1:
2H3PO4+3Ca(OH)2=Ca3(PO4)2+6H2O
m(Ca(OH)2)—>v
v(Ca(OH)2)=m(Ca(OH)2)/M
v(Ca(OH)2)=7.4/74=0.1
v(H3PO4)=0.07
m(H3PO4)=v(H3PO4)*M=0.07*98=7 г
Отв. 2:
x моль 0,1 моль
2H3PO4 + 3Ca(OH)2 => Ca3(PO4)2 + 6H2O
2 моль 3 моль
Находим химическое количество гидроксида кальция
n(Ca3(OH)2) = m (Ca3(OH)2) : M (Ca3(OH)2) = 7,4г : 74 г/моль = 0,1 моль
Из уравнения находим x моль
x моль = (0,1 моль * 2 моль) : 3 моль = 0,06 моль это химическое количество фосфорной кислоты, т.е. n (H3PO4)
Находим массу фосфорной кислоты
m(H2PO4) = n(H3PO4) * M(H3PO4) = 0.06 моль * 98 г/моль = 6,5 г.
ответ: m(H2PO4) = 6,5 г.
1,4 х1 х2
Ca(OH)2+H2-->Ca+2H2O
m(прим)=120×0,11=13,2г
m(Ca(OH)2)=120-13,2=106,8
n(Ca(OH)2)=106,8:74≈1,4моль
х1=1,4
х2=2,8
V(H2)=1,4×22,4=31,36л
m(H2O)=2,8×18=50,4г