# chemistry

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find (i) the total no. of neutrons and (ii) the total mass of neutrons in 7mg o^14C. (assume that the mass of a neutron = mass of a hydrogen atom)

• chemistry -

mols = grams/molar mass
0.007g/14 = ? mols C14 atoms
There are 7 neutrons/atom; therefore,
# mols x 7 = ? mols neutrons.
There are 6.02E23 neutrons for each mol of neutrons; therefore,
mols neutrons x 6.02E23 neutrons/mol = # neutrons.

mass of those neutrons = # neutrons x mass of H atom.

• chemistry -

In 14g of 14^C,no.of neutrons =8NA
In 1g of 14C,no.of neutrons =8NA/14

1)the total no.of neutrons in 7mg of 14^C= 7/1000×4/7×6×10^20
=24×10^20
2)given mass of a neutron=mass of 1 Hydrogen atom=1 amu
Mass of 24×10^20 neutrons=1×24×10^20×1.6×10^-24 g
=0.0004 g

• chemistry -

Are you from resonance?

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