Answer: Option (b) is the correct answer.
Explanation:
A chemical reaction in which heat energy is absorbed by the reactant molecules is known as an endothermic reaction.
Therefore, upon completion of this reaction the container in which reaction is carried out becomes colder.
A chemical reaction in which heat energy is released by the reactant molecules is known as an exothermic reaction.
Therefore, upon completion or during this type of reaction the container in which reaction is carried out becomes hot.
Thus, we can conclude that when the test tube gets colder as the reaction takes place then it means this chemical reaction is endothermic reaction.
Answer:
There are 2 atoms in NaCl. This is because there is 1 atom of Na (sodium) and 1 atom of Cl (chlorine) in each NaCl molecule. Elements by themselves do not have a "number of atoms"- if you're talking about the atomic number, it's the number of protons (or electrons in a neutral atom) of an element.
Answer:
B. Distance from earth. I'm pretty sure. From what I learned it should be that.
For the answer to the question above,
The re<span>action of solid iron with aqueous copper sulfate is an example of a single displacement type of reaction which exchanges only the cations of the element and the compound. In this case, the equation is
Fe (s) + CuSO4 (aq) = FeSO4 + Cu (s) </span>
