va rog ajutatima cu tema la chimie
Răspunsuri la întrebare
Răspuns:
Explicație:
1.
n= m : M
a.
MCaO= 40 + 16=56------->56g/moli
n= 5,6g : 56g/moli= 0,1moli CaO
b.
156g Al(OH)3
M= 27 + 3.16 + 3= 78-------> 78g/moli
n= 156g : 78g/moli= 2moli Al(OH)3
2.
a.
m= n .M
MHNO3= 1 + 14 + 3.16=63------> 63g/moli
m= 6moli .63g/moli= 378g HNO3
b.
3,5kmoli MgO= 3500moli MgO
MMgO= 24 + 16=40-----> 40g/moli
m= 3500moli .40g/moli= 140000g = 140kg MgO
3.
4kmoli N2= 4000moli N2
1mol N2----------6,022.10²³ molcule N2
4000 moli -----------------------x
x= 4000 . 6,022.10²³=24,088.10²³molecule N2
4.
a.
H : C : O =1 :6 : 24= 2 : 12 : 48 ------> H2CO3
b.
Mg : O : H = 12: 16 : 1 = 24 : 32 : 2 -------> Mg(OH)2
5.
25% H si 75% C
M= 16g/moli
formula
100g subt. -------25% H--------75% C
16g------------------x-----------------------y
x= 16 . 25 : 100 = 4g H
y= 16 .75 : 100 = 12g C
formula ----> CH4