Find odd one out for (Air, salt solution, sandwich)​

In this reaction n2o4(g)→2no2(g) what changes in color would you expect as pressure is increased at a constant temperature

How air particles exert a pressure on the inside of the balloon

The diagram shows the relationship between scientific disciplines. the names of some scientific disciplines have been removed from the boxes. which scientific discipline belongs in the blue box? a. physics b. biology c. chemistry d. metallurgy