(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

In manufacture of nitric acid, ammonia and prehated air are mixed to form a gas containing 10 mole %NH3 at 650 C. If ammonia enters the gas blending unit at 25C at a rate o 520kg/? and heat is lost from the mixer to its surroundings at a rate of 7 kW, determine the temperature to which the air must be preheated.

Cpair(kg/molC) = 0.02854 + 0.4147x10^-5T + 0.3191x10^-8T^2 - 1.9665x10^-12T^3

Cpammonia(kg/molc) = 0.03515 + 2.954x10^-5T + 0.4421x10^8T^2 - 6.686x10^12T^3

2. Relevant equations

'0.02894 * (650 - T) + (0.4147 * 10.^-5 .*(650-T).^2) / 2 + (0.3191 * 10.^-8 *(650-T).^3)/3 -(1.965 *10.^-12 * (650-T).^4)/4'

I need to get the T from this equatio but I could not succeed.

I tried solve fnc and etc but no work.

Here is my full code in matlab

===========================

F = '0.03515 + 2.954 .*10.^-5 * t + 0.4421 .*10.^-*8 .t^2 - 6.686 .*10.^-12.*t.^3'

cp = '(0.03515 + 2.954 .*10.^-5 )* t + (0.4421 .*10.^-8) .*-t.^2 - (6.686 .*10.^-12).*t.^3'

integral = quad(cp,25,650)

% -7 -Q = nDH(for air)

Q = 520/17.*integral

nDH = -7 - Q %hava için Delta H değeri

nair = (27/17 * 100/10)*90/100;

knownIntegral= '0.02894 * (650 - T) + (0.4147 * 10.^-5 .*(650-T).^2) / 2 + (0.3191 * 10.^-8 *(650-T).^3)/3 -(1.965 *10.^-12 * (650-T).^4)/4'

I need to get T from here ??

at final step , I need one of the limits of an integral. I know the integral

Pleae I need help on this..

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# Homework Help: How to get one variable from one equation?

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