Chemical reactions are basically divided into two major classes depending on whether the reaction lose energy or gain energy from the environment during the course of the reaction. The two classes of reaction are exothermic and endothermic reaction.
An exothermic reaction is a type of reaction in which the reaction system lose energy to the environment and thus, the energy content of the reactants is more than that of the product formed. Because of this, the enthapyl change of an exothermic reaction is always negative.
An endothermic reaction is a type of reaction in which the reaction system absorb energy from the environment. Thus, the energy contents of the products is always higher than that of the reactants and the enthapyl change of the reaction is always positive. During the course of the reaction, the reaction container is usually cold to the touch because energy is been absorbed from the environment.
I would have helped but I didn’t understand it sorry that I didn’t answer :(
<span>number of moles are the amount of substance of an element .
number of moles can be calculated as follows;
number of moles = mass present / molar mass of element
molar mass of Ar - 40 g/mol
number of moles of Ar = 22 g / 40 g/mol = 0.55 mol .
there are 0.55 mol of Ar</span>
Answer : Option C) Categoric.
Explanation : According to the question the researcher is studying the science of attractiveness and the test is conducted by the volunteers by showing the images of different people, so here we can judge that the study is gender based and has to include male or female. Hence, it can be called as categoric variable.
Answer: An acid-base reaction is the transfer of a proton from a proton donor ... The reaction between a Brønsted-Lowry acid and water is called acid ionization.
Explanation:
