Which of the following compounds will burn with a brick-red colour in a non-luminous Bunsen flame?

The question is asking which of the given compounds will burn with a brick-red color in a non-luminous Bunsen flame. The correct answer is CaCl2. When a compound is burned in a Bunsen flame, the heat causes the electrons in the compound to become excited and emit light. The color of the flame depends on the types of electrons present in the compound and the energy required to excite them. Calcium chloride (CaCl2) is known to burn with a brick-red color in a non-luminous Bunsen flame. This is because the calcium ions (Ca2+) emit light at a specific wavelength, which appears as a brick-red color. The other compounds listed (LiCl, NaCl, MgCl2) do not emit light in the same way and will not produce a brick-red color in a Bunsen flame.