You are conducting a calorimetry experiment using a calorimeter with 500mL of water in its outer chamber to determine the enthalpy of reaction of a chemical reaction. The initial temperature of the water is 25°C. After the reaction, the temperature of the water is 62.8°C. Disregarding any heat loss to the walls of the container, calculate the ΔHr0. The specific heat of water is 4.18J/(g•K).

Astudent made a graph plotting the progress of a reaction over time. the student forgot to label the y-axis of the graph. a graph is shown with two graph lines. one graph line starts at a higher position on the y axis and slopes downwards towards the right. the other graph line starts at a lower position on the y axis and slopes upwards towards the right. the two graph lines stop short of intersecting each other and continue as separate lines which gradually become straight and parallel to the x axis. a vertical line is shown at a point where the two graph lines finally became parallel to the x axis. this vertical line is labeled equilibrium. the title on the x axis is time and an arrow pointing towards the right is shown above time. the title on the y axis is left blank. what best explains the label that the student should use on the y-axis? amount, because as the amount of product decreases, the amount of reactant increases over time. reaction rate, because forward and backward reaction become equal at equilibrium. amount, because the amounts of reactants and products become constant after equilibrium is reached. reaction rate, as the rate of forward reaction increases and rate of backward reaction decreases over time.

You open a can of soda at room temperature and hear a hiss. which of the following factors has changed inside the container? a.) atmospheric pressure b.) temperature of gas c.) type of gas d.) amount of gas

Jenny wants to test the electrical conductivity of two substances dissolved in water. she is preparing the containers for the experiment. which factor is most important for her to control?