A 2.65 g sample of potassium nitrate is dissolved in 114 g of water. What is the percent mass by mass for the resulting solution? Add your answer

3. Un mol de un gas ideal se expande reversiblemente a partir de una presión inicial de 10.0 atm hasta una presión final de 0.4 atm, manteniéndose la tempera-tura constante en 273 K, determine:a) El cambio en la energía interna del gas.b) El trabajo hecho por el gas al expandirse.c) El calor transferido durante el proceso *

\( \mathrm{H}_{3} \mathrm{PO}_{4}(\mathrm{aq})+\mathrm{H}_{2} \mathrm{O}(1) \rightleftharpoons \mathrm{H}_{2} \mathrm{PO}_{4}^{-}(\mathrm{aq})+\mathrm{H}_{3} \mathrm{O}^{+}(\mathrm{aq}) \) In the reaction stated above, what happens when more \( \mathrm{H}_{2} \mathrm{PO}_{4}^{-}(\mathrm{aq}) \) is added to the solution? View Available Hint(s) The equilibrium shifts to the left, producing more \( \mathrm{H}_{3} \mathrm{PO}_{4}(\mathrm{aq}) \). The equilibrium shifts to the right, creating more \( \mathrm{H}_{3} \mathrm{PO}_{4}(\mathrm{aq}) \). The equilibrium shifts to the right, creating more \( \mathrm{H}_{3} \mathrm{O}^{+}(\mathrm{aq}) \). The equilibrium shifts to the left, producing more \( \mathrm{H}_{3} \mathrm{O}^{+} \).

The half-life of Radium- 226 is 1590 years. If a sample contains 500 mg , how many mg will remain after 3000 years? Give your answer accurate to at least 2 decimal places.

4. Considere un sistema que contiene un \( \cdots \) mol de un gas que no puede escapar debido a la acción de un pistón. ¿Cuál es el cambio de temperatura del gas al ser sometido a un pro-ceso donde q \( =50.0 \mathrm{~J} \) y w = 100.0 J ? * -4 K 45 K \( -350^{\circ} \mathrm{C} \)

The half-life of Palladium-100 is 4 days. After 16 days a sample of Palladium- 100 has been reduced to a mass of 6 mg . What was the initial mass (in mg ) of the sample? What is the mass (in mg ) 6 weeks after the start? You may enter the exact value or round to 4 decimal places.