The most common method astronomers use to determine the composition of stars, planets, and other objects is spectroscopy. This process utilizes instruments with a grating that spreads out the light from an object by wavelength. This spread-out light is called a spectrum. Every element has a unique fingerprint that allows researchers to determine what it is made of.
The fingerprint often appears as the absorption of light. Every atom has electrons, and these electrons like to stay in their lowest-energy levels. But when photons carrying energy hit an electron, they can push it to higher energy levels. This is absorption, and each element’s electrons absorb light at specific wavelengths related to the difference between energy levels in that atom. But the electrons want to return to their original levels, so they don’t hold onto the energy for long. When they emit the energy, they release photons with exactly the same wavelengths of light that were absorbed in the first place. An electron can release this light in any direction, so most of the light is emitted in directions away from our line of sight. Therefore, a dark line appears in the spectrum at that particular wavelength.
Because the wavelengths at which absorption lines occur are unique for each element, astronomers can measure the position of the lines to determine which elements are present in a target. The amount of light that is absorbed can also provide information about how much of each element is present.
Answer:

Explanation:
SO in order to calculate the specific latent heat of fusion, you need to remember the formula:

Where
representes the specific latent heart of fusion.
represents the heat energy added, usually represented in kJ
represents the mass of the object, in kg.
Now that we have our formula we just have to put our values into the formula:



SO our answer would be 
Answer:
please the answer Is false
Answer:
cuerpo flota o se hunde es su densidad con respecto a la del líquido en que se sumerge. En cambio, una nuez (densidad = 0.5) flotara en ambos líquidos mientras que una piedra (densidad = 2) se hundirá.
Explanation:
:)
However <em>trans</em>-2-Butene does not give a characteristic peak in 1620-1680 cm⁻¹ region but still the presence of carbon double bond carbon can be detected by detecting following peaks in IR Spectrum.
1) 3010-3100 cm⁻¹:
As in trans-2-Butene a hydrogen atoms ate attached to sp² hybridized carbon, therefore the stretching of =C-H (C-H) bond will give a peak of medium intensity in the range of 3010-3100 cm⁻¹.
2) 675-1000 cm⁻¹:
Another peak which is given by the bending of =C-H (C-H) bond with strong intensity will appear in the range of 675-1000 cm⁻¹.