A set of charged plates have an

The heat of reaction or enthalpy of reaction (ΔH) is the amount of heat energy that the system must release or absorb so that the temperature remains constant throughout the chemical reaction process. In other words, the heat of reaction or enthalpy of reaction (ΔH) is the change in the enthalpy of a chemical reaction (the energy absorbed or released into it) that occurs at a constant pressure.

Then, this energy can be observed in the following way:

Every substance has a quantity of energy stored in its links. When the energy contained in the reagents is greater than that contained in the products, the reaction is exothermic because energy release occurs. When the energy contained in the reagents is less than that contained in the products, an endothermic reaction occurs because energy absorption occurs.

That energy contained in the substances is called enthalpy (H).

Then the enthalpy can be defined as the difference between the sum of the enthalpies of the products and the sum of the enthalpies of the reactants.

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3 years ago

If you travel from Yakima to Ellensburg (Yakima to Ellensburg is 50 miles) with a speed of 60 miles/hour for half of the

koban [17]

Answer:

$\displaystyle \frac{480}{7}\approx 68.6\; \rm mph$ .

Explanation:

The average speed of an object is equal to total distance over total time.

Distance traveled: $\rm 50 \; mi$ .

How much time is taken? This trip is divided into two halves, each of distance $\displaystyle \frac{50}{2} = 25\;\rm mi$ .

Time spent on the first half of the trip:

$\displaystyle t_1 = \frac{s_1}{v_1} = \frac{25}{60} = \frac{5}{12}\; \rm hours$ .

Similarly, time spent on the second half of the trip:

$\displaystyle t_2 = \frac{s_2}{v_2} = \frac{25}{80} = \frac{5}{16}\; \rm hours$ .

In total:

$\displaystyle \frac{5}{12} + \frac{5}{16} = \frac{35}{48} \; \rm hours$ .

Average speed:

$\begin{aligned} \text{Average speed} &= \frac{\text{Total Distance}}{\text{Total Time}}\\ &= 50 \left/\frac{35}{48}\right.\\ &= 50 \cdot \frac{48}{35} \\&= \frac{480}{7}\approx 68.6\; \rm mph \end{aligned}$ .

This value turned out to be slightly different from the average of the speed during the two halves of the journey. The reason is that the object traveled at each speed for a different amount of time. It spent more time at the slower speed, which gives that speed a greater weight in the average. That explains why the average speed is closer to $\rm 60\; mph$ rather than $\rm 80\; mph$ .