Question

During heating, Ti undergoes allotropic transformation from hcp to bcc at 882 °C. The percent volume change accompanying this transformation is \(\underline{\hspace{2cm}}\) (round off to 1 decimal place).

Hint:

For allotropic transformations, calculate the percent volume change using the difference in volumes of the two phases.

Answer 1

Correct Answer: 3.4

The volume change can be calculated using the density of Ti in both phases. First, calculate the volume change:
\[ \Delta V = \frac{V_{\text{bcc}} - V_{\text{hcp}}}{V_{\text{hcp}}} \times 100 \] Using the data for the atomic weights and densities of hcp and bcc Ti:
\[ \Delta V \approx 3.4 \, %. \] Thus, the percent volume change is approximately \( 3.4 \, % \).