Maybe the first or third ☝️ one
Answer: The molarity of an HCl solution is 0.218 M if 43.6 mL of a 0.125 M NaOH solution are needed to titrate a 25.0 mL sample of the acid.
Explanation:
Given:
= 43.6 mL,
= 0.125 M
= 25.0 mL,
= ?
Formula used to calculate the concentration of acid is as follows.

Substitute the values into above formula.

Thus, we can conclude that the molarity of an HCl solution is 0.218 M if 43.6 mL of a 0.125 M NaOH solution are needed to titrate a 25.0 mL sample of the acid.
This is so frustrating I don’t even understand this
Answer:
Humidity is the amount of moisture (water vapor) in the air. It can be expressed as absolute humidity or relative humidity. Absolute humidity is the mass of water vapor divided by a unit volume of air (grams of water/cm3 of air).
A cation is smaller than its parent atom.
Therefore, here a sodium ion is smaller than the neutral sodium atom.
Reason: Since the sodium atom loses an electron to form an electropositive ion(cation), its nuclear charge increases(the number of protons exceeds the number of electrons) and the orbital electrons are pulled with a greater energy.
Thus,the sodium ion shrinks in size.