Science is a continuous profession of study because new ideas are produced based on new evidence. Also, there are different topics of science such as climate change or new cures to different diseases.
Decomposition reaction D. 2H20⇒ 2H2 + O2
<h3>Further explanation
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Every chemical reaction involves a compound consisting of reactants and products
Reactants are compounds that react and form new compounds called products
There are several forms of reactions that can occur, including single replacement, double replacement, synthesis, decomposition, etc.
A. 2C2H6 + 702 ⇒ 4CO2 + 6H20
Combustion : reaction of Hydrocarbon and Oxygen
B. AgNO3 + LiCl → AgCl + LINO3
Double replacement : there is an ion exchange between two ion compounds in the reactant to form two new ion compounds in the product
C. Ca + MgS → CaS + Mg
Single replacement :one element replaces the other elements of a compound to produce new elements and compounds
D. 2H20⇒ 2H2 + O2
Decomposition : One compound breaks down into 2 components
The answer is: II.The endpoint is recorded when the solution is dark red in color rather than light pink.
The endpoint is the point at which the indicator changes colour in a colourimetric titration and that is point when titration must stop.
Phenolphthalein is colorless in acidic solutions and pink in basic solutions. If this indicator change color to dark red, more base is added and endpoint is not accurate.
If the the acid is spilled before titration, that does not make endpoint wrong and molar mass can be calculated.
In this example we can take acetic acid as carboxylic acid; basic salt sodium acetate CH₃COONa is formed from the reaction between weak acid (in this example acetic acid CH₃COOH) and strong base (in this example sodium acetate NaOH).
Balanced chemical reaction of acetic acid and sodium hydroxide:
CH₃COOH(aq) + NaOH(aq) → CH₃COONa(aq) + H₂O(l).
Neutralization is is reaction in which an acid (in this example vinegar or acetic acid CH₃COOH) and a base react quantitatively with each other.
D. All of the above. Developing medicine, analyzing compounds and producing new product such as plastic all have to deal with chemistry.
