It is 3 cause they are all the same leatheth so 3
Answer:
The standard enthalpy of formation is the energy that would be involved if one mole of the substance were to be formed from its elements that were at standard conditions of temperature and pressure which are 25 degrees C and one atm pressure.
Step-by-step explanation:
Answer: The number is: "2 " .
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Explanation:
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Write the expression; which is an equation, as follows:
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" 4x <span>− 12 = 2(-x) " ; in which "x" represents "the number for which we shall solve" .
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Note:
If the "number" = "x" ; the "opposite of the number" = " -x " ;
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Rewrite as: " 4x <span>− 12 = -2x " ;
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→ Add "12" ; & add "2x" ; to EACH SIDE of the equation:
4x − 12 + 12 + 2x = -2x + 12 + 2x ;
to get: 6x = 12 ;
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Now, divide each side of the equation by "6" ;
to isolate "x" on one side of the equation; & to solve for "x" ;
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6x / 6 = 12 / 6 ;
to get: x = 2 .
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Answer: The number is: "2 " .
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Let us check our answer, by plugging in "2" for "x" in our original equation:
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→ " 4x − 12 = 2(-x) " ;
Let us plug in "2" for "x" ; to see if the equation holds true; that is; if both side of the equation are equal; when "x = 2" ;
→ " 4(2) − 12 = ? 2(-2) ??
→ 8 − 12 = ? -4 ? ;
→ -4 = ? -4 ?? Yes!
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Answer:
The father is 40 and the son is 4.
Step-by-step explanation:
40 + 5 = 45.
4 +5=9.
45 divided by 5 = 9
At the start, the tank contains
(0.02 g/L) * (1000 L) = 20 g
of chlorine. Let <em>c</em> (<em>t</em> ) denote the amount of chlorine (in grams) in the tank at time <em>t </em>.
Pure water is pumped into the tank, so no chlorine is flowing into it, but is flowing out at a rate of
(<em>c</em> (<em>t</em> )/(1000 + (10 - 25)<em>t</em> ) g/L) * (25 L/s) = 5<em>c</em> (<em>t</em> ) /(200 - 3<em>t</em> ) g/s
In case it's unclear why this is the case:
The amount of liquid in the tank at the start is 1000 L. If water is pumped in at a rate of 10 L/s, then after <em>t</em> s there will be (1000 + 10<em>t</em> ) L of liquid in the tank. But we're also removing 25 L from the tank per second, so there is a net "gain" of 10 - 25 = -15 L of liquid each second. So the volume of liquid in the tank at time <em>t</em> is (1000 - 15<em>t </em>) L. Then the concentration of chlorine per unit volume is <em>c</em> (<em>t</em> ) divided by this volume.
So the amount of chlorine in the tank changes according to

which is a linear equation. Move the non-derivative term to the left, then multiply both sides by the integrating factor 1/(200 - 5<em>t</em> )^(5/3), then integrate both sides to solve for <em>c</em> (<em>t</em> ):


![\dfrac{\mathrm d}{\mathrm dt}\left[\dfrac{c(t)}{(200-3t)^{5/3}}\right]=0](https://tex.z-dn.net/?f=%5Cdfrac%7B%5Cmathrm%20d%7D%7B%5Cmathrm%20dt%7D%5Cleft%5B%5Cdfrac%7Bc%28t%29%7D%7B%28200-3t%29%5E%7B5%2F3%7D%7D%5Cright%5D%3D0)


There are 20 g of chlorine at the start, so <em>c</em> (0) = 20. Use this to solve for <em>C</em> :

![\implies\boxed{c(t)=\dfrac1{200}\sqrt[3]{\dfrac{(200-3t)^5}5}}](https://tex.z-dn.net/?f=%5Cimplies%5Cboxed%7Bc%28t%29%3D%5Cdfrac1%7B200%7D%5Csqrt%5B3%5D%7B%5Cdfrac%7B%28200-3t%29%5E5%7D5%7D%7D)