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Is this true or not

1u=1.660*10-27kg

 relative mass of the Li=7u=1 atom=1.660*10-27*7kg

7g=6.022*1023 atoms of Li

1kg=1000g

1.660*10-27*7kg=1.660*10-27*7*1000g

1g=(1.660*10-27*7)/(1.660*10-27*7000)

7g={(1.660*10-27*7)/(1.660*10-27*7000)*7} kg

1.660*10-27*7kg=1 atoms 

1kg=1/1.660*10-27*7 atoms 

{(1.660*10-27*7)/(1.660*10-27*7000)*7} kg=(1/1.660*10-27*7)*{(1.660*10-27*7)/(1.660*10-27*7000)*7}atoms= 6.022*1023

Is this true or not

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1 Answer

What, exactly, are you asking? Is what true? This is very convoluted.

There are errors in the calculations above:

line 2, the mass of an atom of Li is 6.94 u, but close enough

line 7, remove the "kg" from the end.

line 9, put parentheses around the denominator, otherwise you'll get an error

In the last statement, it looks like what you're saying is:

7 g = 6.022 x 10^23 atoms, which is true. 7 g is the molar mass of Li, which means that 7 g Li = 1 mol Li = 6.022 x 10^23 atoms Li.