Examlex
The mass spectrum of an element with two naturally occurring isotopes is shown below.What is the best estimate of the element's atomic mass?
Purity
The state of being free from contamination, pollution, or other unwanted elements; often used in a moral or spiritual context to denote cleanliness or innocence.
Colour
The characteristic of visual perception described in terms of hue, lightness, and saturation, which objects produce by the way they reflect or emit light.
Physical Property
A characteristic of a substance that can be observed or measured without changing the substance's identity.
Impossible Figures
Optical illusions or drawings of objects that appear to be real and three-dimensional but are geometrically impossible to exist in reality.
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