АААААААААААААААААА ЛЛЛЛЮЮЮДДДИИИИ ССРРРОООЧЧЧЧНННОООООО ППППОООООММММОООГГГИИИТТТЕЕЕ
1)рассчитайте массу и объем (н.у)7.224 *10 в 22 степени молекул сероводорода
2)определите массу железа содержащуюся в 1т чугуна имеющего 8% примисей
3)какую массу фосфорной кислоты и воды следует взять для приготовления 450г ее 15%-го раствора помогите плиз
1)n(H2S)=N/N(A)=7.224*10^22/6.02*10^23=0.12моль
M(H2S)=34г/моль
V(H2S)=22.4*0.12=2.688л
m(H2S)=34*0.12=4.08г
2)1т=1000кг
если 8% примесей, то масса железа 100-8=92%(0.92)
m(Fe)=1000*0.92=920кг=0.92т
3)m(H3PO4)=0.15*450=67.5г
m(H2O)=450-67.5=382.5г
Автор:
victoriaxtuwДобавить свой ответ
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