Answer:
D.
They have a positive charge and are present in the nucleus of an atom along with the neutrons.
explanation:
Protons have a positive charge.
Answer:
leave little space between the molecules.
Explanation:
Matter is made up of small particles called molecules. These molecules present in matter are arranged inside its bulk.
In liquids and solids, the molecules are arranged very close together in such a way that there is only a little space between them. This is why liquids and solids are referred to as "condensed phases".
They are quite unlike gases where there is a lot of space between gas molecules.
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The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to an atom or molecule making a transition from a high energy state to a lower energy state. The photon energy of the emitted photon is equal to the energy difference between the two states. There are many possible electron transitions for each atom, and each transition has a specific energy difference. This collection of different transitions, leading to different radiated wavelengths, make up an emission spectrum. Each element's emission spectrum is unique. Therefore, spectroscopy can be used to identify elements in matter of unknown composition. Similarly, the emission spectra of molecules can be used in chemical analysis of substances.