Question

Which one is more acidic?
A.Lime
B.Gastric Juice
C.Water
D.Lemon

Answer 1

Any chemical with a pH of zero to seven is considered acidic, whereas those with a pH of seven to fourteen are termed bases. An acid is referred to as a proton donor, whereas a base is referred to as a proton acceptor. Pure water is neutral, meaning it is neither acidic nor basic.

Complete answer: The pH scale, which stands for 'potential of hydrogen' or 'power of hydrogen,' is a chemical scale that is used to quantify the acidity or basicity of an aqueous solution. Acidic solutions (those containing a larger concentration of $H^+$ ions) have a lower pH than basic or alkaline solutions. The pH scale is logarithmic, indicating the concentration of hydrogen ions in a solution in inverse order. Because the pH formula approximates the negative of the base 10 logarithm of the molar concentration of hydrogen ions in the solution, this is the case. pH is defined as the negative of the base 10 logarithm of the $H^+$ ion's activity.
At $25^oC$, acidic solutions have a pH less than 7, while basic solutions have a pH greater than 7. At this temperature, pH 7 solutions are neutral (e.g. pure water). The pH neutral value changes with temperature, becoming lower than 7 as the temperature rises. For highly strong acids, the pH value can be less than 0 and for very strong bases, it can be larger than 14.

COMPOUND	pH	INFERENCE
Water	7	Neutral
Gastric Juice (conc HCl)	1	Highly acidic
Lime	9	Alkaline
Lemon	4	Acidic

Hence option D is Correct.

Note:
Water, hydrochloric acid, electrolytes (sodium, potassium, calcium, phosphate, sulphate, and bicarbonate), and organic compounds make up gastric juice (mucus, pepsins, and protein). Because of the hydrochloric acid concentration, this juice is very acidic and abundant in enzymes.