I think it's calorie
Hope this helps
Endothermic reactions and Exothermic reaction are never the same.
They are both different.
Definitions
<span><span>Endothermic:- reactions that take in energy. For example:- electrolysis, thermal decomposition and the reaction between ethanic acid and sodium carbonate.
</span><span>Exothermic:- reactions that transfer energy to the surroundings. For example:- burning, neutralisation and the reaction between water and calcium oxide.</span></span>
Agar is used to assist establish an anaerobic environment that promotes nitrate reduction.
Nitrate Reduction test:
- The nitrate in the broth is converted to nitrite by organisms that can produce the nitrate reductase enzyme, which can then be further converted to nitric oxide, nitrous oxide, or nitrogen.
- Anaerobic respiration and denitrification are two processes that can convert nitrate to a variety of compounds.
- While denitrification only reduces nitrate to molecular nitrogen, anaerobic respiration employs nitrate as the bacterium's final electron acceptor, reducing it to a range of chemicals.
- The nitrate reduction test is based on the detection of nitrite and its capacity to produce a red precipitate (prontosil), which is a water-soluble azo dye, when it combines with sulfanilic acid to create a complex (nitrite-sulfanilic acid).
Learn more about the Nitrate reduction test with the help of the given link:
brainly.com/question/11181586
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