Question

Cati moli si molecule sunt in 300g Ca CO LA a3a
Ce masă si nr de molecule sunt in 3 moli mg (OH) 2

Answer 1

300g CaCO3

moli

nr. molecule

MCaCO3=40+12+3. 16=100---------> 100g/moli

n=m  : M    [ n=nr moli ;  m=masa subst.  ;     M=masa molara ]

n= 300 g : 100g/moli=3 moli CaCO3

1mol CaCO3-----------6,023.10²³ molecule

3moli---------------------------x

x=3  .  6,023 .10²³ molecule=

3moli Mg(OH)2

g  Mg(OH)2

nr.molecule

M=24+2.16 + 2=58--------58g/moli

m=n.M

m=3moli . 58g/moli=172 g

1mol Mg( OH )2--------------6,023 .10²³ molecule

3moli----------------------------x

x=3 . 6,023.10²³ molecule =