Step 1: Analyze the properties of alkali metal bicarbonates. Alkali metal bicarbonates typically form solids except for lithium bicarbonate (\({LiHCO}_3\)), which cannot be isolated as a solid under normal conditions and typically exists only in solution.
Step 2: Choose the correct option based on known chemical properties. Lithium bicarbonate's inability to form a solid is due to its highly soluble and unstable nature in solid form compared to other alkali metal bicarbonates like sodium (\({NaHCO}_3\)) or potassium (\({KHCO}_3\)) bicarbonates.