Flame Colors

Flame Colors as Chemical Indicators

火焰颜色作为化学指示剂

Though not as definitive as the spectral fingerprints from atomic spectra, the colors produced by chemicals when inserted into a flame can be used to identify some constituents of minerals. One procedure used was to put a small amount of the chemical on a small loop of platinum wire and place it into the open flame from a laboratory burner.

虽然不如原子光谱的特征光谱 definitive，但将化学物质放入火焰中产生的颜色可以用来识别矿物的一些成分。一种使用的方法是将少量化学物质放在一小段铂丝上，然后放入实验室燃烧器的开放火焰中。

Several types of wire were tried, but all produced prominent colors of their own. Platinum was the only one tried which would glow red hot without producing any appreciable plume of color in the flame. If the platinum wire were touched with your fingers, then you would get a colored plume, notably sodium presumed to come from our hands. After that burned off, just the bright tip of the wire loop was visible.

尝试了多种类型的导线，但所有导线本身都会产生明显的颜色。铂是唯一一种在不产生火焰中明显颜色的情况下能红热发光的导线。如果将铂导线触碰手指，就会产生一种颜色，明显是来自我们手上的钠。燃烧过后，只可见导线环的明亮尖端。

NaCl

SrCl₂

BaSO₄

Sodium chloride at left gave the brightest light, much brighter than the blue flame of the burner. The color is visually the same as other sodium lights, coming mainly from the sodium d-lines. The brilliant red of strontium is the most dramatic of the flame colors. At right above is a sample of barium sulfate (barite) mineral, which gave only a small amount of light which was almost white.

左边的氯化钠发出最亮的光，比烧瓶的蓝色火焰明亮得多。这种颜色在视觉上与其他钠光相同，主要来自钠的D线。锶的鲜艳的红色是火焰颜色中最引人注目的。右上方是巴里特矿（硫酸钡）的样本，它只发出少量的光，几乎呈白色。

All of the above flames were obtained from a natural potassium chloride (sylvite) sample. The two at left are more like the classical textbook colors for potassium. But the variety of colors at right makes it clear why the students argue over whether the color is pink or violet. The flames at right are much brighter, as you can see by comparing their brightness to that of the flame from the burner. It may be that there is some contaminant in those at right, like sodium?

上述所有火焰均来自天然的氯化钾（岩盐）样品。左边的两种火焰更接近教科书上记载的钾的经典火焰颜色。但右边颜色的多样性清楚地说明了为什么学生会争论这种颜色是粉红色还是紫色。右边的火焰亮度更高，你可以通过将其亮度与烧气炉的火焰进行比较来确认。也许右边的火焰中含有一些杂质，比如钠？

These are flame colors from azurite, a copper-containing mineral. It gave better copper color than malachite, to our surprise.

这些是来自蓝铜矿的火焰颜色，这是一种含铜的矿物。令人惊讶的是，它比孔雀石能给出更鲜艳的铜色。

Potassium chloride in mineral form gave the distinctive potassium color.

矿物形式的氯化钾呈现出独特的钾色。