A student receives three materials and must determine whether each is a metal or nonmetal. To do this, the student performs three tests on each material. First, the student cleans each material, examines the surface, and records any observations, Next, the student takes a small sample of each material, strikes the sample with a hammer, and records any observations. Lastly, the student attaches a piece of
wax to a long, thin sample of the material and heats the end opposite of the wax. The student records the amount of time it takes for the wax to melt. The table shows the results of the three tests.
Material
Surface
Struck with
Time for Wax

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.

you didnt put any of the following

on passing the small ampere of electric current through the tube made of ar and hg of cfl generates uv rays which excites the fluorescent and thus emits the high radiation by consumption of just 5- 12 w in comparison to incandescent light which requires more power such as around 40 - 55 w to lighten.

moreover the life span of fluorescent or cfl is around 8000 h whereas the life span of incandescent is around 1200 h

hence, the building installed with incandescent lights bears more electricity bill.