2Na + Cl₂ → 2NaCl
Explanation:
The reaction of sodium metal with chlorine gas to produce sodium chloride is a typical example of synthesis reaction.
Combination or synthesis involves the formation of a single product from two or more reactants.
A + B ⇒ C
In this kind of chemical reaction, a single product is formed or some compounds by the union of elements is notable.
The driving force for this category of chemical reaction is the large and negative heat of formation of the product.
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Chemical reaction brainly.com/question/3953793
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Apply conservation of energy; the pendulum's maximum potential energy (at the highest point of its motion) equals the maximum kinetic energy (at the lowest point of its motion):
Max PE = Max KE
We will calculate the max PE, ie the potential energy after that ball is lifted up:
Max PE = mgh
PE is the potential energy, m is the ball's mass, g is acceleration due to earth's gravity, and h is the height.
Given values:
m = 2kg
g = 9.81m/s²
h = 1.5m
Plug in the values and solve for Max PE:
Max PE = 2(9.81)(1.5)
Max PE = 29.43J
The ball's kinetic energy is given by:
KE = 0.5mv²
We know the ball's velocity is greatest when it attains Max KE, and the max KE equals the Max PE:
Max KE = Max PE = 29.43J = 0.5mv²
Given values:
m = 2kg
Now plug in and solve for v:
2v² = 58.86
v = 5.425
v = 5.4m/s
Answer:
4.0 m/s
Explanation:
In the first part of the run, the athlete runs a distance of
![d_1 = 300 m](https://tex.z-dn.net/?f=d_1%20%3D%20300%20m)
at a speed of
![v_1 = 3.0 m/s](https://tex.z-dn.net/?f=v_1%20%3D%203.0%20m%2Fs)
So, the time he/she takes is
![t_1 = \frac{d_1}{v_1}=\frac{300}{3.0}=100 s](https://tex.z-dn.net/?f=t_1%20%3D%20%5Cfrac%7Bd_1%7D%7Bv_1%7D%3D%5Cfrac%7B300%7D%7B3.0%7D%3D100%20s)
In the second part of the run, the athlete covers an additional distance of
![d_2 = 300 m](https://tex.z-dn.net/?f=d_2%20%3D%20300%20m)
with a speed
![v_2 = 6.0 m/s](https://tex.z-dn.net/?f=v_2%20%3D%206.0%20m%2Fs)
So, the time taken in this second part is
![t_2 = \frac{d_2}{v_2}=\frac{300}{6.0}=50 s](https://tex.z-dn.net/?f=t_2%20%3D%20%5Cfrac%7Bd_2%7D%7Bv_2%7D%3D%5Cfrac%7B300%7D%7B6.0%7D%3D50%20s)
So, the total distance covered is
d = 300 m + 300 m = 600 m
And the total time taken
t = 100 s + 50 s = 150 s
Therefore, the average speed for the entire trip is
![v=\frac{d}{t}=\frac{600}{150}=4.0 m/s](https://tex.z-dn.net/?f=v%3D%5Cfrac%7Bd%7D%7Bt%7D%3D%5Cfrac%7B600%7D%7B150%7D%3D4.0%20m%2Fs)
<span>The maximum possible efficiency, i.e the efficiency of a Carnot engine , is give by the ratio of the absolute temperatures of hot and cold reservoir.
η_max = 1 - (T_c/T_h)
For this engine:
η_max = 1 - [ (20 +273)K/(600 + 273)K ] = 0.66 = 66%
The actual efficiency of the engine is 30%, i.e.
η = 0.3 ∙ 0.664 = 0.20 = 20 %
On the other hand thermal efficiency is defined as the ratio of work done to the amount of heat absorbed from hot reservoir:
η = W/Q_h
So the heat required from hot reservoir is:
Q_h = W/η = 1000J / 0.20 = 5000J</span>
D. is the answer to your question