Nobelium-259 is a radioactive substance that decays according to the following function, where \( y_{0} \) is the initial amount present, and \( y \) is the amount present at time \( t \) (in minutes). \[ y=y_{0} e^{-0.0119 t} \] Find the half-life of Nobelium-259. Do not round any intermediate computations, and round your answer to the nearest tenth.

Question 5 What is the pH of a solution, having the \( \mathrm{H}_{3} \mathrm{O}^{+} \)concentration of \( 7.06 \mathrm{e}-9 \mathrm{M} \) ? Add your answer

3. จงอ่านชื่อของสารประกอบต่อไปนี้ 3.1 Bas

3. จงอ่านชื่อของสารประกอบต่อไปนั้ 3.1 Bas \( 3.2 \mathrm{Mg}\left(\mathrm{HCO}_{3}\right)_{2} \) 3.3 ZnO \( 3.4\left(\mathrm{NH}_{4}\right) \mathrm{HPO}_{4} \) \( 3.5 \mathrm{~K}_{2}\left(\mathrm{CO}_{4}\right. \)

A substance with a pH of 2 is

You can also do the reverse, calculate the \( \mathrm{H}_{3} \mathrm{O}^{+} \)molarity from the pH , using the formula \( \mathrm{H}_{3} \mathrm{O}^{+} \)molarity \( =10^{-}-\mathrm{pH} \) What is the \( \mathrm{H}_{3} \mathrm{O}^{+} \)molarity of a solution having the pH of 2.56 ?