Answer:
The mass of water that will evaporate 2.857 kg.
Explanation:
Given;
temperature of the water, T = 100 c
rate of heat transfer, H = 2 kW = 2000 w
time, t = 10 min = 10 min x 60s = 600s
heat capacity of water is given by;
Q = McΔT
Where;
Q is the quantity of heat transfer to the pan = P x t = 2000 x 600 = 1200000 J.
c is specific heat capacity of water = 4200 J/kg.°C
m = (Q) / (cΔT)
m = (1200000) (4200 x 100)
m = 2.857 kg
Therefore, the mass of water that will evaporate 2.857 kg.
The balanced equation of the combustion of the propane is

From the above chemical equation, it is clear that 1 mole of propane requires 5 moles of oxygen to undergo complete combustion as the result of this reaction, 3 moles of carbon-di-oxide and 4 moles of water molecules will be produced.
Therefore one-half mole of propane requires 2.5 moles of oxygen to undergo complete combustion. And in the reaction, 1.5 moles of carbon-di-oxide and 2 moles of water molecules are produced.
Therefore the answer is, 'One-half of propane combines with 2.5 moles of oxygen to produce 2 moles of water and 1.5 moles of carbon dioxide'
Answer:
Q=mc∆tita.
4780J= m × 2445J/kg/°C × 5.43°C
4780J= m× 13276.35J/kg
m= 0.36Kg
For physics, I would recommend to just keep doing practice problems and reviewing notes. Repetition of the same concepts will help drill it into your brain. Hope that helps!
Answer: vf = 51 m/s
d = 112 m
Explanation: Solution attached:
To find vf we use acceleration equation:
a = vf - vi / t
Derive to find vf
vf = at + vi
Substitute the values
vf = 3.5 m/s² ( 8.0 s) + 23 m/s
= 51 m/s
To solve for distance we use
d = (∆v)² / 2a
= (51 m/s - 23 m/s )² / 2 ( 3.5 m/s²)
= (28 m/s)² / 7 m/s²
= 784 m/s / 7 m/s²
= 112 m