Investigate Flame Colors of Different Cations When they were heated by Fire. &
Testing changes of cations using sodium hydroxide (NaOH) aqueous
Aims & Objectives
Different characteristic cations will form different colors when they are burned or added base. In these two experiments, scientist took some sample of barium hydroxide (Ba (OH) 2·H2O), ferric chloride (FeCl3·6H2O), copper chloride (CuCl2· 2H2O), calcium chloride anhydrous (CaCl2), potassium carbonate crystal (K2CO3· 2H2O), strontium chloride hexahydrate (SrCl2· 6H2O), lead nitrate (Pb (NO3) 2), sodium chloride (NaCl) and magnesium chloride hexahydrate (MgCl2· 6H2O). In the first experiment, scientist used wet splint to dip in the powder of those samples above. The independent variable is different cations and using DI water to wet splints. In addition, the dependent variable is the flame color of different cation. In the second experiment, scientist used plastic burettes to drop 2ml sodium hydroxide firstly and secondly drop excess sodium hydroxide to observe changes of color of cations. The independent variable is different cations and added DI water into the test tube as well as the dependent variable is the color changes of adding sodium hydroxide.
My aim of these experiments is to find out the colors of different cations. There is no accurate value, the number. The results are qualitative, and they are not very accurate. The data results are only the word, which used to describe the color, such as red, blue, green and other colors. The way scientist used to reduce error was to observe the color for a longer time, hold the fire on, pour out some rest cation powder from the gas burner and add excess sodium hydroxide at every second time.
In the first experiment, there are only physical reactions. Those cations released energy when they were heated No new product is reacted, so there is no chemical reaction. When substances of cations are burned, the electrons...
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