Answer : The scientific theory is considered to be the foundation of many science experiments because it has well supported theory related reproducible data of test table, experiments,etc. which are usually valid and is of great help in predicting reactions.
Also these scientific theories are considered to be robust, durable and can be changed as and when required; because of its flexibility in accepting a modification/change or addition to the previous theory. All of these reasons contribute to develop scientific theories into a stronger and longer durable one.
<u>Answer:</u> 
of the reaction will be negative, 
of the reaction will be positive and 
of the reaction will be negative.
<u>Explanation:</u>
Thermodynamic properties are enthalpy change 
, entropy change 
and Gibbs free energy
Exothermic reactions are defined as the reactions in which energy is released in the form of heat. The enthalpy change of the reaction comes out to be negative for this kind of reaction.
Entropy change is defined as the change in the measure of randomness in the reaction. It is represented as . Randomness of gaseous particles is more than that of liquid which is further more than that of solids.
For the given exothermic reaction:
As, number of gaseous particles on the product side is more than the number of gaseous particles on the reactant side. So, the entropy change is positive. Hence, is positive.
The above reaction is spontaneous. Thus, the Gibbs free energy will be negative.
For the given reaction:
<span>Filtration, if its a precipitate that means its insoluble. </span>
The correct answer is 2.
In oxidation-reduction reactions (or redox reactions), a number of electrons are transferred between two species. During this process, the oxidation number of an atom (or molecule or ion) changes by receiving or losing an electron.
The answer is <span>a total of eight valence electrons
hope this help
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