A reaction in which heat is evolved is an exothermic reaction while a reaction in which heat is absorbed is an endothermic reaction.
In the first case; Na2CO3 + H2SO4, we can see that this is an acid - base reaction therefore it is a neutralization reaction. Since the tube was hot after reaction, heat is given off so it is exothermic.
In the second case; NaOH + H2SO4, we can see that this is an acid - base reaction therefore it is a neutralization reaction. We are told that the tube is not hot but we don't know the initial temperature of the tube or if it was colder than it's initial temperature so we can not make any inference regarding whether the reaction is endothermic or exothermic.
Lastly, the reaction, NaCl + HC2H5OH does not occur so we mark "no reaction". We are told that the tube is not hot but we don't know the initial temperature of the tube or if it was colder than it's initial temperature so we can not make any inference regarding whether the reaction is endothermic or exothermic.
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F-1 because there is a one after it.
Answer:
A chemical change can be indicated by a change in color, change in temperature (exothermic or endothermic), change in smell, formation of a precipitate, or the formation of gas bubbles.
Explanation:
this should work
Explanation:
Unordered items;
cell, elephant, human body, school bus, organ ,molecule.
This problem deals with the organization of life. We move from cells, to tissues, organs, and then systems.
Molecule
Cell
Organ
Human body
Elephant
School bus
School bus is the largest from the giving items although it is non-living.
