Chromium (Cr): 2, 8, 8, 6
Copper (Cu): 2, 8, 8, 11
Chromium+2 (Cr+2): 2, 8, 8, 4 (if the ion retains a positive charge then the amount of electrons will decrease)
Copper+2 (Cu+2): 2, 8, 8, 9
Manganese+2 (Mn+2): 2, 8, 8, 5
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.
2H2+O2→2H2O
We have to be aware that the number of atoms are the same on both reactant side and product side.
Answer:
The final temperature of the system is 42.46°C.
Explanation:
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.
where,
c = specific heat of water= 
= mass of water sample with 100 °C= 50.0 g
= mass of water sample with 13.7 °C= 100.0 g
= final temperature of system
= initial temperature of 50 g of water sample= 
= initial temperature of 100 g of water =
Now put all the given values in the given formula, we get
The final temperature of the system is 42.46°C.
Answer:
Is there a question you need help with?
