Thermo Review

Solve for the standard enthalpy of reaction (ΔH). Determine if the reaction is endothermic or exothermic.

What is the formula for calculating heat?

Consider the reaction: 2 H₂O + energy --> 2H₂ + O₂

Experimental Set-up for Calories in a Chocolate Chip Cookie Students designed an experiment to determine the amount of calories in a chocolate chip cookie. A ring stand was used with a clean aluminum soda can hung from the ring that was partially filled with a known mass of water. A thermometer was placed inside the can so that it measured the temperature of the water but did not touch any part of the metal can. Once set-up was complete, an initial water temperature was taken. The cookie was then lit on fire and allowed to completely burn. A final temperature of the water was measured.

Refer to the experimental set-up for calories in a chocolate chip cookie. How does this experiment allow students to measure the calories in a cookie?

Between which points is the temperature of the substance remaining constant?