ΔH<span> for the reaction = [sum of heat of formation for products] - [sum of heat of formation for reactants]
-6534 = [(12)(-393.5) + (6)(-285.8)] - (2X)
-6534 = [(-4722) + (-1714.8)] - 2X
-6534 = -6436.8 - 2X
-6534 + 6436.8 = -2X
-</span>97.2 = -2X<span>
then, divide each side by two to cancel out the numerical coefficient.
x = +48.6 kJ, which is the heat of formation for benzene.</span>
Answer:
The force is 
Explanation:
The diagram for this question is shown on the first uploaded image
At Equilibrium the summation of the of force on the vertical axis is zero
i.e 
=> 
is the is the speed of water at the nozzle which can be mathematically evaluated as

substituting
for R and
for


is the is the speed of water at the pipe which can be mathematically evaluated as

substituting
for R and
for


is he density of water with value 
Substituting values into the equation above


At Equilibrium the summation of the of force on the horizontal axis is zero
i.e 
=> 
Since The speed at both A and B nozzle are the same then
remains the same
Substituting values

=> 
Hence the force acting on the flange bolts required to hold the nozzle in place is



Answer:
3MgCl2 has 9 atoms.
Explanation:
The Element Magnesium (Mg) has 3 atoms.
The Element Chloride (Cl) has 6 attoms.
Their fore 6 + 3 is 9 of course. 3MgCl2 has 9 atoms.
BTW: 3MgCl2 is a molecular compound as well as H2O and CO2.
Answer:
14.7 m/s.
Explanation:
From the question given above, the following data were obtained:
Time (t) = 1.5 s
Acceleration due to gravity (g) = 9.8 m/s².
Height = 11.025 m
Final velocity (v) = 0 m/s
Initial velocity (u) =?
We, can obtain the initial velocity of the penny as follow:
H = ½(v + u) t
11.025 = ½ (0 + u) × 1.5
11.025 = ½ × u × 1.5
11.025 = u × 0.75
Divide both side by 0.75
u = 11.025/0.75
u = 14.7 m/s
Therefore, the penny was travelling at 14.7 m/s before hitting the ground.