N_a is the flux it can be related from J_a. Na is not avogadro's number they got it wrong on the last try. (dr) = delta radius Mw is molecular weight. dt is delate time. I need to start from the basic flux equation. Please need help with this problem

I know that C_a = y_aC that is how I sub delta(y_a) for where the concentration should go. Please solve this formula using this set up. Thank you

N_a(flux) = (N_a +N_B)y_a - D_ABC(dy_a/dr)

This is the general formula we need to solve with integratio

A sphere of naphthalene of 6cm diameter is sublimated in stagnant air. Derive the equation AND calculate the half-life time of this sphere (the time it takes for the sphere to have a diameter of 3cm ). Additional information: Air is at 113F and 1atm. The molecular weight and density of naphthalene are 128g/mol and 71.1lb/ft3, respectively. The vapor pressure of naphthalene these conditions is 0.8mmHg. Diffusion of naphthalene in air at 45C is 6.92106m2/s. You will derive the equation starting from the two equations derived in class: odr=NAMWdt(1)NAr2=r0DABCln(1yAsat1) You have to replace (2) in (1) and solve the integral with limits t=0 to t=t1/2 and r=r0 to r= o /2 This is the final solution: 21=(7ro2)(24DABCMWln(1yAsat1)) BE SURE THAT YOU UNDERSTAND HOW EQUATIONS (1) and (2) WERE DERIVED