OCR Gateway Chemistry controlled assessment research

reaction has taken place, for example a gad is given off or a solid is

This reaction is exothermic, as heat is given out. This is because the amount reactant energy is more than the product energy the difference between this is ΔH, therefore some energy has been given out in the form of

Endothermic reactions are accompanied by the absorption of heat. The dissolving of ammonium nitrate in water is an example of an endothermic reaction. The solution resulting from this mixture is colder than either the ammonium nitrate or the water. This is the simple explanation of what happens in an instant ice pack. The more detailed information will be discussed in the following paragraphs.

This reaction is exothermic, meaning it releases heat when reactants are converted into products. The negative change in enthalpy (∆H° = -36,757 J) for this reaction indicates that the reaction is losing heat to its surroundings.

In this experiment you will observe some physical and some chemical changes. You will observe that energy must be used to start some chemical reactions, and that it is produced in others.

In this unit we have conducted research and experiments on our chosen reactions to create the highest exothermic reaction for the The Heat-and-Eat meal pack will use a chemical reaction that involves two reactants. Reactant 1 is a solid and Reactant 2 is a liquid.

Chemical reactions that release energy are called exothermic reactions, these reactions are observed by an increase in temperature of the reaction mixture.

Once you fill this tumbler with either tea, coffee, milkshake, soda, lemonade or any other kind of drink. The drink will stay as cold or as hot as the science of thermodynamics will allow, for as many hours as possible.

Cellular respiration is also a chemical reaction that releases heat. The following graph explains cellular respiration very well. It looks complicated but you will get to understand it later as we explore more

* This system was designed to help stop the reaction if too much heat was generated.

As mentioned, this reaction is a type of single replacement reaction, and all single replacement reactions are exothermic, meaning they produce heat. This is because in the reaction:

Introduction: The theory behind this experiment is the heat of a reaction (∆E) plus the work (W) done by a reaction is equal to

Aim: To find out what type of insulation holds the most heat for a can

Background: Energy changes occur in all chemical reactions; energy is either absorbed or released. If energy is released in the form of heat, the reaction is called exothermic.

Purpose: This lab taught procedures for determining heat of capacity of a calorimeter and measuring enthalpy of change for three reactions. It also enforced methods of analyzing data obtained through experimentation and calculating enthalpy. These procedures are used in the branch of thermodynamics known as thermochemistry which is the study of energy changes that accompany chemical reactions. Concepts from this lab can be used to determine the potential energy of a chemical reaction. Much of the energy people depend on comes from chemical reactions. For example, energy can be obtained by burning fuel, metabolizing of food or discharging a batter.