Answer:
B. Composed of molecules relatively far apart.
Explanation:
The gas we call "air" has molecules that are relatively far apart.
The first practical incandescent light bulb<span>. </span>Edison<span> and his team of researchers in </span>Edison's<span> laboratory in Menlo Park, N.J., tested more than 3,000 designs for </span>bulbs<span> between 1878 and 1880. In November 1879, </span>Edison<span> filed a patent for an electric </span>lamp<span> with a carbon filament.</span>
You should never taste anything in a lab.
Litmus paper will only tell you whether it is an acid or a base, not how strong it is a hydrogen test only works with acids.
You can get a serious burn from touching strong acids and bases and it doesn't give an objective measure of the strength.
The only one that is left is conductivity. This is safe and rather reliable, because the "strength" of an acid or a base depends on how much it dissociates. Hence more dissociation means greater conductivity.
Lighting a match changes chemical energy into heat.
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