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 answer is B, you just check if it is the same on the left and right side
A:
Left side - Right side
2xH - 2xH
1xS - 3xS
4xO - 12xO
2xAl - 2xAl
Therefore A is not correct
B:
Left side - right side
2xK - 2xK
1xCl - 1xCl
1xPb - 1xPb
2xN - 2xN
6xO - 6xO
B is therefore correct as both sides add up
The answer is 2 atm. I guessed on the problem and got it right. I don’t know the work though.
Answer:
The internal combustion engine in the car converts the potential chemical energy in gasoline and oxygen into thermal energy which is transformed into the mechanical energy that accelerates the vehicle (increasing its kinetic energy) by causing the pressure and performing the work on the pistons.
Explanation:
Answer:
0.00007975 mole
Explanation:
Number of moles can be calculated as; mass of solute/volume of solvent or concentration of solution x volume of that solution.
In this case:
Concentration of solution = 1.45 M
Mass of solvent (water in this case) = 55.0 mg
55.0 mg of water is equivalent to 0.55 ml of water.
Therefore, volume of solution = 0.055 ml
Hence, number of moles of solute = molarity x volume
1.45 x 0.000055 = 0.00007975 mole
