Question

Calculeaza numarul de molecule si numarul total de atomi din:
c)19,6 kg acid sulfuric
d)80 kg troxid de sulf
e)2 kmoli heliu

Answer 1

19,6 kg H2SO4 =19600 g

MH2SO4=2+32 + 4.16=98 --------> 98g/moli

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

n=19600g : 98g/moli=200 moli H2SO4

1mol H2SO4----------6,023.10²³molecule ---------7 . 6,023.10²³ atomi

200moli---------------------x-----------------------------------y

x=200.6,023.10²³molecule=1204,6 .10²³ molecule

y=200.  7  .6,023.10²³ atomi =8432,2 .10²³ atomi

80 kg SO3=80000g SO3

MSO3=32+ 48=80--------> 80g/moli

n=m:M

n=80000g: 80g/moli=1000moli SO3

1molSO3--------------6,023.10²³ molecule ----------4  . 6,023.10²³atomi

1000 moli----------------------x---------------------------------y

x=1000 . 6,023.10²³ molecule=6023 .10²³molecule

y=1000.  4 .  6,023.10²³ molecule=

2kmoli He=2000 moli He

1mol He-----------------6,023.10²³molecule ----------6,023.10²³atomi

2000 moliHe-----------------x---------------------------------y

x=2000.6,023.10²³=12046 .10²³ molecule

y=2000.6,023 .10²³=12046 .10²³ atomi