Answer:
It’s A
Explanation:
The nights are shorter. I just took the unit test review
Answer:
Explanation:
heat released by the solution
= 120 x 3.18 x ( 25 - 14 )
= 4197.6 J
= 4.1976 kJ
This is the heat gain by the salt
so enthalpy change = + 4.1976 kJ
because there is increase in enthalpy
It is endothermic process .
Answer:
Explanation:
These instrument works on the analysis of the emisson spectral of light received from the star in this way.
Think of a steel knife in your kitchen. Initially, it has this shiny silver colour that typifies it. When the knife is placed on a hot plate, it becomes hotter and begins to go red as the heating continues. If we stop the heating and pour cold water on it, the red dissapears and our knife is back to itself, although the silvery shine would be lost. This is simply how the atomic absorption spectroscopy works. When you see the hot knife you can say a couple of things about it. Different metals have their various melting point. We can compare the temperature at which our knife will melt with a standard melting point scale to know the type of metal it is made of.
In atomic absorption spectroscopy, an atom gains energy and it becomes excited. Every atom is known to have a peculair amount of absorbant energy that cause them to excite. The more the particles in the atom, the more the energy required. When we analyse the absorbent energy of the atom, it differs from other atoms and we truly identify such an atom even if we don't know it. Most times, the energy is given off as light.
