Answer:
The noble gases (Group 18) are located in the right of the periodic table and were previously referred to as the "inert gases" due to the fact that their filled valence shells (octets) make them extremely nonreactivE
Explanation:
Answer: he expected to find no darkening of the film all because it hadn't been exposed to sunlight yet.
13) "..From the ___" My guess would be Sun since it says solar later in the question. Then an example of solar energy would be flashlights, thermostats (etc..)
14) Mechanical
16) Conductors, (Ex. copper, metal)
17) Insulators, most non metallic materials (Ex. cloth, or rubber, plastic)
18) Electrocution
