Hi Yogesh,
I live in Scotland so don't have much experience of temperatures that high, but as Spaniel Crazy has said, it is a bit unusual for her tongue to become paler when she is panting heavily (I think you would expect it to go darker as more blood is pumped by the increased heart beat).
The panting by itself is a reaction to the heat - does your house have air conditioning? Does she have easy access to water? Maybe you could keep water cool for her by dropping a few ice cubs in it from time to time.
If her tongue is going paler in the heat, it suggests to me either that the blood is being diverted to other organs as a reaction to the heat, or for some reason her circulatory system isn't working as efficiently under the heat-stress conditions.
I think you would be wise to speak to your vet. They will presumably be dealing with all the pets in your area who are living in the same conditions and will be the best placed to know what is normal and what is not, and will no doubt have some good advice.