What does a flame test indicate about the energy changes?
The colors observed during the flame test result from the excitement of the electrons caused by the increased temperature. The electrons “jump” from their ground state to a higher energy level. As they return to their ground state, they emit visible light.
What is the main limitation of flame tests?
Limitations of the Flame Test The test cannot detect low concentrations of most ions. The brightness of the signal varies from one sample to another. For example, the yellow emission from sodium is much brighter than the red emission from the same amount of lithium. Impurities or contaminants affect the test results.
What color does the flame turn when potassium chloride is inserted?
light lilac
Is a blue flame dangerous?
A blue flame means complete combustion is taking place. The above are all indications of incomplete combustion. The result is that you could be wasting gas and/or generating dangerous carbon monoxide. The latter is a serious safety problem, if it occurs with an indoor appliance.
Is a blue flame hotter?
The color blue indicates a temperature even hotter than white. Blue flames have more oxygen and get hotter because gases burn hotter than organic materials, such as wood. When natural gas is ignited in a stove burner, the gases quickly burn at a very high temperature, yielding mainly blue flames.
What is the coldest flame?
The lowest recorded cool flame temperatures are between 200 and 300°C; the Wikipedia page references n-butyl acetate as 225°C. You can read a lot more about cool flames on that page.
What produces the hottest flame?
The hottest fires are from oxyacetylene torches (about 3000 degrees Centigrade) that combine oxygen and gas to create pinpoint blue flames. Color also tells us about the temperature of a candle flame. The inner core of the candle flame is light blue, with a temperature of around 1800 K (1500 °C).
What makes a flame purple?
Potassium salts produce a characteristic purple or violet color in a flame.
What burns with a green flame?
Because each element has an exactly defined line emission spectrum, scientists are able to identify them by the color of flame they produce. For example, copper produces a blue flame, lithium and strontium a red flame, calcium an orange flame, sodium a yellow flame, and barium a green flame.