1 files changed, 40 insertions, 0 deletions
diff --git a/3763/CH12/EX12.8/Ex12_8.sce b/3763/CH12/EX12.8/Ex12_8.sce
new file mode 100644
index 000000000..68515b1cd
--- /dev/null
+++ b/3763/CH12/EX12.8/Ex12_8.sce
@@ -0,0 +1,40 @@
+clear
+//
+//
+//
+
+//Variable declaration
+dz1=4*10**-18    //diffusivity(m**2/s)
+dz2=5*10**-13    //diffusivity(m**2/s)
+T1=773    //temperature(K)
+T2=1273   //temperature(K)
+T3=573   //temperature(K)
+T4=973   //temperature(K)
+
+//Calculation
+x1=(log(dz1))
+
+y1=(log(dz2))
+
+x2=(-1/(8.314*T1))
+
+y2=(-1/(8.314*T2))
+
+x=((x1-y1))
+
+y=((x2-y2))
+
+Q=x/y      //activation energy(J/mol)
+z=(y1-(y2*Q))
+
+D0=exp(z)          //diffusion coefficient(m**2/Vs)
+D1=D0*exp(-Q/(8.314*T3))    //diffusivity at 300 C(m**2/s)
+D2=D0*exp(-Q/(8.314*T4))    //diffusivity at 700 C(m**2/s)
+
+//Result
+printf("\n activation energy is %0.3f  kJ/mol",Q/10**3)
+printf("\n answer varies due to rounding off errors")
+printf("\n diffusion coefficient is %0.3f  *10**-4 m**2/s",D0*10**4)
+printf("\n diffusivity at 300 C is %0.2f  *10**-23 m**2/s",D1*10**23)
+printf("\n diffusivity at 700 C is %0.3f  *10**-15 m**2/s",D2*10**15)
+printf("\n answer given in the book is wrong")