Question

Find the number of electrons in a drop of h2so4weighing4.9×10^-3mg.

Answer 1

Answer:

150.5×10^17 electrons

Explanation:

no of eletrn

atomic no =no of prtns=no of elctrns

h is 1

s is 16

o is 8

2 atoms of h

2×1

1 atom of s

1×16

4 atoms of o

4×8=32

total number of elctrns

32+2+16=50 electrns

no of moles of h2so4

4.9×10^-3 mg to g

4.9×10^-6g

molar mass of h2so4 is 98g/mol

no of moles=mass/molar mass

=4.9×10^-6/98=0.05×10^-6mol

1 compound of h2so4 have 50 electrns

so 0.05×10^-6moles of h2so4 have

50×0.5×10^-6mol

=25×10^-6mol

1mol=6.022×10^23electrns

25×10^-6×6.02×10^23=150.5×10^17 electrons