Volume change during heating

When iron is heated, it undergoes a change from the bcc structure to fee at 910°C. In these forms, the unit cell constants are 363 pm and 293 pm, respectively. By what percent does the volume change during the phase transition What would be the change in density ... 

Flow many phases exist at a triple point Describe what would happen if a small amount of heat were added under constant-volume conditions to a sample of water at the triple point. Assume a negligible volume change during fusion. 

Gas volume changes during chemical reactions are responsible for the inflation of air bags in vehicles. Sodium azide is made for use in car air bags. When this compound is heated to 300 °C it rapidly decomposes into its elements according to the following equation ... 

Adiabatic elasticity, Q, measured under such conditions that no heat is allowed to enter, or escape from, the fluid during the volume change. 

In order to illustrate how the mode of operation can positively modify selectivity for a large reactor of poor heat-transfer characteristics, simulations of the reactions specified in Example 5.3.1.4 carried out in a semibatch reactor were performed. The reaction data and process conditions are essentially the same as those for the batch reactor, except that the initial concentration of A was decreased to cao = 0.46 mol litre, and the remaining amount of A is dosed (1) either for the whole reaction time of 1.5 h with a rate of 0.1 mol m s", or (2) starting after 0.5 h with a rate of 0.15 mol m " s". It is assumed that the volume of the reaction mixture and its physical properties do not change during dosing. The results of these simulations are shown in Fig. 5.3-15. The results of calculation for reactors of both types are summarized in Table 5.3-3. 

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