Answer:
a) 1512000 Joules
b) 5040 seconds = 84 minutes = 1.4 hours
Explanation:
Power saved y replacing bulbs = 60-18 = 42 W = 42 J/s
Time the bulb is used for = 10 hours
Energy saved during this time
42×10×60×60 = 1512000 Joules
Saved energy by replacing standard incandescent lightbulbs with energy-efficient compact fluorescent lightbulbs in 10 hours is 1512000 Joules
b) Power the plasma TV uses = 300 W = J/s
\frac{1512000}{300}=5040\ s3001512000=5040 s
Time a plasma TV can be used for with the saved energy is 5040 seconds = 84 minutes = 1.4 hours.
When Newlands tried to create a periodic table, his tried to conform to the "Rule of Octaves" he had discovered. He had the right idea, in that if you arrange the elements by atomic weight there would be similarities every 7 elements (not 8 because noble gases hadn't been discovered yet) but he tried to push this rule so much that he would put multiple elements in the same box to try to keep the rule. Mendeleev, however, left gaps in this table for undiscovered elements, which paved the way for our modern periodic table.
Answer:
Protons have a much larger volume than neutrons.
Electron requires energy to move from ground state to excited state(higher energy levels). Hence option 1 is correct. Hope this helps!