MY and \( \text{NY}_3 \), two nearly insoluble salts, have the same \( K_{\text{sp}} \) values of \( 6.2 \times 10^{-13} \) at room temperature. Which statement would be TRUE in regard to MY and \( \text{NY}_3 \)?

For MY, \( S_1 = \sqrt{K_{\text{sp}}} \), and for \( \text{NY}_3 \), \( S_2 = (K_{\text{sp}}/27)^{1/4} \). Calculating gives \( S_1 > S_2 \), hence the molar solubility of MY is greater, making the solubility of MY less than \( \text{NY}_3 \) incorrect, wait: \( S_1 \) is larger, so MY is more soluble than \( \text{NY}_3 \). Thus, molar solubility of MY in water is greater, which means option 4 says less, let's check common ion effect: addition of \( \text{KY} \) decreases solubility due to common ion effect. The molar solubility of MY in water \( \approx 7.8 \times 10^{-7} \), while \( \text{NY}_3 \approx 1.15 \times 10^{-3} \), so MY molar solubility is less than \( \text{NY}_3 \).