Which statement is not correct about acid-base

Question

If the pH of a solution of HCl is 4, what is its H₃O⁺ concentration (in mol/L)?

1. 0.6128
2. 6.1 × 10^-1
3. 4.0 × 10^-5
4. 1.0 × 10^-4

When added to an aqueous solution, fatty acids arrange themselves in the form of:

1. Micelles
2. Detergents
3. Glycolipids

Which statement is not correct about acid-base chemistry?

1. The larger the Ka, the stronger the acid
2. A small pKa correspond to a small Ka
3. The smaller the pKa, the stronger the acid