Alpha particles are relatively heave and can be stopped by a sheet of paper.
Wind ,ice,and water eroded it over years
Science is a continuous profession of study because new ideas are produced based on new evidence. Also, there are different topics of science such as climate change or new cures to different diseases.
Weight percentage of nitrogen can be calculated using the following rule:
weight percentage of nitrogen = (weight of nitrogen / weight of urea) x 100
From the periodic table:
molecular mass of carbon = 12 grams
molecular mass of nitrogen = 14 grams
molecular mass of hydrogen = 1 grams
molecular mass of oxygen = 16 grams
therefore:
mass of nitrogen in urea = 2(14) = 28 grams
mass of urea = 12 + 2(14) + 4(1) + 16 = 60 grams
Substitute with the masses in the equation to get the percentage:
weight percentage of nitrogen = (28/60) x 100 = 46.667%
The correct answer is D<span>) remains hazardous for a long time. Nuclear waste stays radioactive for many centuries.
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This is generally buried underground, so it does not cause significant air pollution, greenhouse effect, or acid rain<span>. These three are mostly caused by particulate matter or greenhouse gases that are emitted into the atmosphere
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