Answer:
D, E and F
Explanation:
About tetrachloro cobalt complexes, the following facts have been observed
- Color of the tetrachloro cobalt complexes is blue.
- They do not decompose on heating that means synthesis of tetra chloro is endothermic.
About hexa aqua cobalt complexes, the following facts have been observed
- Color of the hexa aqua cobalt complexes is pink color.
- They decompose on heating and remain stable on cooling that means process of synthesis of hexa aqua cobalt complexes is exothermic.
Based on above, the correct statements are:
The correct is chloro cobalt complex is blue and aqua cobalt
complex is pink.
The chloro complex is favored by heating.
If the chloro complex is a product, then the reaction must be endothermic.
The correct options are D, E and F.
True. The building blocks of life are atoms
We know 1 mole of any atom or molecules contains 
atom or molecules.
1 mole of HBr i.e 81 gm/mol contains atom or molecules.
So, mass of 
molecules is :
Therefore, mass of molecules is 1.21 gm .
Hence, this is the required solution.
False
only observing chemical property will change its identity
Answer: D.
Explanation: D. Acetone, Acetone may be rinsed over materials to wash off the explosive residue.
Hope this helps :)
