In order to calculate the mass of nitrogen, we must first calculate the mass percentage of nitrogen in potassium nitrate. This is:
% nitrogen = mass of nitrogen / mass of potassium nitrate
% nitrogen = 14 / 101.1 x 100
The mass of nitrogen = % nitrogen x sample mass
= (14 / 101.1) x 101.1
= 14 grams
The molar weight of nitrogen is 14. Each mole of urea contains two moles of nitrogen. Therefore, for there to be 14 grams of nitrogen, there must be 0.5 moles of urea.
Mass of urea = moles urea x molecular weight urea
Mass of urea = 0.5 x 66.06
Mass of urea = 33.03 grams
Answer:
B extinction
Explanation:
as the species does not exist any more, the species is extinct, therefore making the pictured fossil of an extinct species
hope this helps
Hello,
<span>B.They have the same number of valence electrons. </span>
Answer:
Explanation:
Let the number of half lives be x
<u>Solve this equation to find the value of x:</u>
- 125*(1/2)ˣ = 3.90625
- (0.5)ˣ = 3.90625 / 125
- (0.5)ˣ = 0.03125
- log (0.5)ˣ = log 0.03125
- x = log 0.03125 / log 0.5
- x = 5
Answer:
Do not try to re-light or handle malfunctioning fireworks. Soak both spent and unused fireworks in water for a few hours before discarding.