Grade 12Physical Chemistry

The number of unit cells in 58.5g of NaCl is nearly

Ananya Rana

10 Years agoGrade 12

3 Answers

SAHIL

10 Years ago

atomic mass of sodium=23 g

this means 23 g has no. of toms=6.022 multiply 10²³

therefore 58.5 g has no. of atoms= 6.022 x 10²³/23 x58.5

therefore no. of atoms in a unit cell of bcc structure=2

there fore no. of unit cell which contains no. of atoms= 6.022 x 10²³ x 58.5/23x2

you wil get the answer.

thanks and approve. you can post answer after calculation . i will tell you whether you have calculated right r wrong

but please approve. thanks again

palak

9 Years ago

it will be same but they have asked unit cell not no. of atoms therefore we will not multiply by 2 only 6.023×10^23×58.5÷23

Rishi Sharma

6 Years ago

Dear Student,
Please find below the solution to your problem.

Molar mass of NaCl ⇒23 + 35.5
=58.5g.
Thus, 58.5 g of NaCl corresponds to 1 mole of NaCl and contains 6.023×10^23 molecules.
One unit cell of NaCl (fcc structure) has 4 NaCl molecules.
Hence, 1 mole of NaCl will contain
= 46.023×10^23
≈1.5×10^23 unit cells.
The number of unit cells in 58.5 g of NaCl is nearly 1.5×1023.

Thanks and Regards