Chemistry Questions

Hybridisation of Ni is e-  

Unpaired 3d8in  is 2 

So $$\begin{gathered} Ω = n(n+2)BM \\ =2x4 = 8 = 2.82BM \end{gathered}$$

When atoms react they do so in order to reach the lowest energy, which is the most stable. The electrons orbitals will overlap in the way that reduces the energy the most. Orbitals of similar energy will produce the greatest stabilisation.The answer you gave isn't the whole story, it depends what species is reacting with what. The effective nuclear charge on the atom will affect the energy of the valance electrons.

Hence, the reactivity of an atom arises from the existence of unpaired electrons in the valence shell.

The process of conversion of milk into curd is called fermentation.  It is a chemical change. Milk consists of globular proteins called casein. As the microorganism lactobacillus react with milk and turn it to curd. For it 37 degree temperature is needed. But sometimes when it does not get favourable condition, then other microorganism react and makes the curd taste different.