<span>molar mass of MgCl2
= 24.32 + 2 x (35.45) = 95.22 g</span><span>
<span>16.4g MgCl2 x (1 mol MgCl2/95.22
g MgCl2) = 0.172 mol MgCl2 </span>
</span>
<span>0.172 mol MgCl2 x (6.022 x 10^23/1 mol
MgCl2) = 10.36 x 10^22 atoms<span> </span></span>
I think it is 4. Covalent compound which is named carbon dioxide.
Answer : The mass of 7.0 m chain is, 15.12 kg
Explanation :
As we are given that,
The weight of the chain per unit length = 2.16 kg/m
Now we have to determine the mass of chain for 7.0 m length.
As, the mass of 1 m length of chain = 2.16 kg
So, the mass of 7.0 m length of chain = 
= 15.12 kg
Therefore, the mass of 7.0 m chain is, 15.12 kg
2NaN3 + H2O —> 2HN3 + Na2O