A system does 125 J of work and cools down by releasing 438 J of heat. The change in internal energy is J.

Given that,

Work done by the system = 125 J

Energy released when it cools down = 438 J

To find,

The change in internal energy.

Solution,

As heat is released by the system, Q = -438 J

Work done by the system, W = -125 J

Using the first law of thermodynamics. The change in internal energy is given by :

So, the change in internal energy is 563 J.

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.