Carbon dioxide is a gas having chemical formula
, a gas which exhaled by humans and inhaled by plants. It is also emitted from the sources such as cement production and combustion of fossil fuels. It is also known as greenhouse gas associated with acidification of ocean.
Carbon dioxide with other gases acts like a blanket of Earth which absorbs infrared radiations emitted from the sun and thus, preventing the escaping of these rays into the outer space which results in the gradual heating of Earth's surface and atmosphere i.e. increase in temperature of Earth. This process is known as Global Warming.
Hence, carbon dioxide is responsible for the increase in warming of the atmosphere i.e. option (D).
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.
A) cesium chloride
B) barium oxide
C) potassium sulfide
D) beryllium chloride
E) hydrogen bromide
F) aluminum fluoride