When 0.514 g of biphenyl (C12H10) undergoes combustion in a bomb calorimeter, the temperature rises from 25.8 C to 29.4 C. Find ⌂E rxn for the combustion of biphenyl in kJ/mol biphenyl. The heat capacity of the bomb calorimeter, determined in a separate experiment, is 5.86 kJ/ C.
<span>The answer is - 6.30 * 10^3 kJ/mol
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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.
Answer:
5
Explanation:
all you do is the math expression
The mass of plutonium that will remain after 1000 years if the initial amount is 5 g when the half life of plutonium-239 (239pu, pu-239) is 24,100 years is 2.5 g
The equation is Mr=Mi(1/2)^n
where n is the number of half-lives
Mr is the mass remaining after n half lives
Mi is the initial mass of the sample
To find n, the number of half-lives, divide the total time 1000 by the time of the half-life(24,100)
n=1000/24100=0.0414
So Mr=5x(1/2)^1=2.5 g
The mass remaining is 2.5 g
- The half life is the time in which the concentration of a substance decreases to half of the initial value.
Learn more about half life at:
brainly.com/question/24710827
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