Answer:
5 g
Explanation:
The heat required to vaporize ice is the sum of
i) Heat required to melt ice at 0°C
ii) Heat required to raise the temperature from 0°C to 100°C
iii) Heat required to vaporize water at 100°C
Thus;
H = nLfus + ncθ + nLvap
H= n(Lfus + cθ + Lvap)
Lfus = 6.01 kJ/mol
Lvap = 41 kJ/mol
c = 75.38
n =?
2100 = n(6.01 + 75.38(100) + 41)
n = 2100 KJ/7585.01 kJ/mol
n = 0.277 moles
Mass of water = number of moles * molar mass
Mass of water = 0.277 moles * 18 g/mol
Mass of water = 5 g
Answer:
We need 10.14 grams of sodium bromide to make a 0.730 M solution
Explanation:
Step 1: Data given
Molarity of the sodium bromide (NaBr) = 0.730 M
Volume of the sodium bromide solution = 135 mL = 0.135 L
Molar mass sodium bromide (NaBr) = 102.89 g/mol
Step 2: Calculate moles NaBr
Moles NaBr = Molarity NaBr * volume NaBr
Moles NaBr = 0.730 M * 0.135 L
Moles NaBr = 0.09855 moles
Step 3: Calculate mass of NaBr
Mass NaBr = 0.09855 moles * 102.89 g/mol
Mass NaBr = 10.14 grams
We need 10.14 grams of sodium bromide to make a 0.730 M solution
Answer:
Explanation:
To solve the problem, we must know the kind of compounds we are dealing with.
For the first compound, P1 and second compound P2:
N O N O
Mass percent 64.17 35.73 47.23 52.79
Atomic mass 14 16 14 16
Number of
moles 64.17/14 35.73/16 47.23/14 52.79/16
4.58 2.23 3.37 3.30
Simplest
ratio 4.58/2.23 2.23/2.23 3.37/3.30 3.3/3.3
2 1 1 1
P1 compound is N₂O
P2 compound is NO
These are the compounds,
In N₂O = 28:16
NO = 14:16
This is the ratio of nitrogen to a fixed mass of oxygen for the two compounds.
Answer:
4m/s in the direction of the turn
Explanation:
The velocity of an object is the rate of change of its position with respect to a frame of reference.
Assuming the runner stays the same speed as he turns, his velocity will be 4m/s in the speed he turns.
Number 9 is A and 10 is A
