Placing sodium metal into water creates a bright light and a lot of heat – an explosion. Sodium metal disappears during this explosion. Is this a chemical change?

Look at the spectrums of a star moving towards earth and a motionless star. which of these is a correct inference that can be draw from the observation of the two spectrums? (2 points) the spectrum of a motionless star is difficult to be viewed separately using oridinary telescopes. the spectrum of a motionless star is identical to the spectrum of a star which moves towards earth. the spectrum of a star shifts towards the red region when the star moves towards earth. the spectrum of a star shifts towards the blue region when the star moves towards earth.

Which characteristics can be used to differentiate star systems? check all that apply.

The chemical bond connecting one nucleotide with the next one along the nucleic acid chain is called a