This chemistry question involves key chemical concepts and calculations. The detailed solution below walks through each step, from identifying the reaction type to computing the final answer.
ScanSolve AI Answer
Step 1: Identify the given radii of the cation and anion. The radius of the cation A^+ (r_c) is 148 \, pm. The radius of the anion B^- (r_a) is 195 \, pm. Step 2: Calculate the radius ratio ((r_c)/(r_a)). (r_c)/(r_a) = 148 \, pm195 \, pm (r_c)/(r_a) ≈ 0.75897 Step 3: Determine the coordination number and crystal structure based on the radius ratio. The radius ratio rules for ionic compounds are: 0.155 - 0.225: Coordination number 3 (Trigonal planar) 0.225 - 0.414: Coordination number 4 (Tetrahedral) 0.414 - 0.732: Coordination number 6 (Octahedral, NaCl type) 0.732 - 1.000: Coordination number 8 (Cubic, CsCl type) The calculated radius ratio of approximately 0.759 falls within the range 0.732 - 1.000. This indicates a coordination number of 8. Step 4: Relate the coordination number to the given options. A coordination number of 8 for an ionic compound typically corresponds to a cubic arrangement, such as the CsCl structure. In the CsCl structure, one type of ion (e.g., cation) is located at the body center of a cube formed by eight ions of the other type (e.g., anions). This arrangement is often referred to as a Body-Centered Cubic (BCC) structure in the context of ionic compounds. Comparing this with the options: (a) Body centred cubic: This matches the expected structure for a coordination number of 8. (b) Face centred cubic: This corresponds to a coordination number of 6 (e.g., NaCl type). (c) Tetrahedral: This corresponds to a coordination number of 4. (d) Octahedral: This corresponds to a coordination number of 6. Therefore, the ionic compound AB will have a Body-Centered Cubic structure. The final answer is a) Body centred cubic.