The energy of an electron in a hydrogen atom is:
<span>E= (-2.179 x 10 ^-18 J)(1/n^2)
</span>where n is the principle energy level of the electron.
<span>
E= (-2.179 x 10 ^-18 J)(1/4)
</span><span>E= -2.179 x 10 ^-18 J
</span>E = -5.4 <span>x 10 ^-19 J</span>
Answer:
D
Explanation:
Solar panels are not toxic, so option A goes out the window.
Aesthetics don't really matter, so option B follows it out.
Option C makes a little sense, but less so than Option D. They aren't nearly as heavy as some of our current energy production methods.
Solar panels are expensive, hard to store properly, and most are between 15 and 20 percent efficiency, compared with a diesel motor's 40 percent.
Answer:
1.96mL
Explanation:
Density = mass/volume, and rearranged to solve for volume, volume = mass/density.
So:
volume = 5.30g/2.70g/mL = 1.96mL (assuming your unit was g/mL for density)