What does below chemistry rebus means?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

Spot what is wrong here in below Picture?

What kind of tree can you carry in your hand?

Below rebus represent famous DiCaprio movie. Can you name it?

Can you solve the tricky chess rebus puzzle below by ciphering the hidden meaning?

Jack was having a candle light dinner with his girlfriend. Suddenly a cold gush of wind entered through the open window and three of the ten candles were extinguished. Assuming that none of the other candles were extinguished.

How many candles are they left with in the end ?

There are forty elephants and they have forty-fore heads. How can this be possible?

If 1+9+8=1, what is 2+8+9?

What number does the below three word/phrase identify and why?
1. Deck
2. Year
3. Singing in the Rain