How many oxygen atoms are located on the reactant side of the following chemical equation? \( \mathrm{C}_{3} \mathrm{H}_{8}(\mathrm{~g})+5 \mathrm{O}_{2}(\mathrm{~g}) \rightarrow 3 \mathrm{CO}_{2}(\mathrm{~g})+4 \mathrm{H}_{2} \mathrm{O}(\mathrm{g}) \)

If 82 g of sugar is dissolved in 7950 mL of water, what is the concentration of the solution?

Actividad 3. Composición porcentual y Rendimiento de Reacción. (15 puntos) 1. Calcula la composición porcentual de cada elemento en los siguientes compuestos: a) \( \mathrm{AgNO}_{3} \) b) \( \mathrm{C}_{2} \mathrm{H}_{6} \mathrm{O} \)

A partir de la siguiente ecuación de combustión de octano, si reaccionan 59.2 gramos de octano, ¿Cuántos gramos de Oxígeno se necesitan? \[ \mathrm{C}_{8} \mathrm{H}_{18}+25 / 2 \mathrm{O}_{2}-\cdots>8 \mathrm{CO}_{2}+9 \mathrm{H}_{2} \mathrm{O} \] Considera: \( \mathrm{C}: 12, \mathrm{O}: 16, \mathrm{H}: 1 \)

A chemist carefully measures the amount of heat needed to raise the temperature of a 510.0 mg sample of a pure substance from \( 2.9^{\circ} \mathrm{C} \) to \( 23.7^{\circ} \mathrm{C} \). The experiment shows that 25.9 J of heat are needed. What can the chemist report for the specific heat capacity of the substance? Be sure your answer has the correct number of significant digits.

A formula connecting density \( (d) \), mass \( (m) \) and volume \( (v) \) is \[ d=\frac{m}{v} \] \( m=30.14 \mathrm{~g} \) after being truncated to 2 d.p. \( v=3.78 \mathrm{~cm}^{3} \) after being truncated to 2 d.p. Calculate the lower and upper bounds of \( d \). Round your answers to \( 2 \mathrm{~d} . \mathrm{p} \).