QUESTION ONE 1. What does quenching mean in luminescence? [2 marks] 2. Define the quantum yield for a photochemical process (2 marks] 3. How would the quantum efficiency of fluorescence be altered (increased, decreased) by changing the factors below? Explain the reasons for your answer. (6 marks] a Lowering the temperature b. Changing the concentration of fluorophore c. Dissolved oxygen Calculate the fluorescence quantum yield of the following two flurophores (A and B) based on the excitation and emission spectra shown below. Indicate which fluorophore A or B will be brighter (5 marks). Flumiplustes Flusstophote B . T) 75 Cunts to 5 75 Wackerth, Balenish, 2