Saved Bookmarks
| 1. |
The viscosity of molten sodium is 4.5 xx 10^(-4) Nm^(-2)sat 473 K and 2.12 xx 10^(-4) Nm^(-2) s at 873 K. Calculate the activation energy for the viscous flow. Also, calculate the viscosity at 673 K. |
|
Answer» Solution :We have, `log eta_(1)/eta_(2) = E/(2.303 R) ((T_(2)-T_(1))/(T_(1)T_(2)))` `log(4.5 xx 10^(-4))/(2.12 xx 10^(-4)) = E/(2.303 xx 8.314) ((873-473)/(473 xx 873))` E=6461 J/mole =6.461 kJ/mole Further, let the viscosity at 673 K be `eta_(2)` Again, we have, `T_(1) = 473 K, eta_(1) = 4.5 xx 10^(-4)` `T_(2) = 673 K, eta_(2)`= ? `log (4.5 xx 10^(-4))/eta_(2) = 6461/(2.303 xx 8.314) ((673-473)/(473 xx 673))` `eta_(2) = (2.76 xx 10^(-4) Nm^(-2)s)` |
|