| A | B |
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| Specific heat is what? | The amount of heat that raises the temperature of 1 g of a substance by 1 degree celsius. |
| Heat is measured in units of ______ ? | Calories (cal) or joules ( J ). |
| Define a calorie. | The amount of heat needed to raise the temperature of exactly 1 g of water by exactly 1 degree celsius. |
| How many calories (cal) in a kilocalorie (kcal)? | 1000 calories = 1 kilocalorie |
| One calorie is equal to how many joules? | 4.18 joules |
| One kilojoule equals how many joules? | 1000 |
| What is also known as the nutritional "big" Calorie? | the kilocalorie (kcal) |
| The heat gain or loss formula is … | Heat gain or loss = (mass) X (temperature change {aka: Delta T}) X (specific heat) |
| Caloric values for the three food types are…? | Carbohydrate = 4 kcal per gram, Fat (lipid) = 9 kcal per gram, protien = 4 kcal per gram. |
| True or false: all reactions occur at the same rate if the temperature is the same. | False. Each reaction occurs at its own rate. |
| The rate (or speed) of a reaction depends on how quickly a ________ ? | reactant or products concentration changes over time. |
| Exothermic or endothermic: Heat raised (feels warm)? | Exothermic |
| Exothermic or endothermic: Heat is a product of the reaction. | Exothermic |
| Exothermic or endothermic: A + B ---> C + heat. | Exothermic |
| Exothermic or endothermic: heat absorbed (feels cool) | Endothermic |
| Exothermic or endothermic: heat is a reactant in the reaction. | Endothermic |
| Exothermic or endothermic: heat + C ---> A + B | Endothermic |
| For a reaction to occur three things must happen. What are they? | 1. The molecules must collide. 2. They must collide effectively (at the proper oreintation). 3. Must collide with the minimum amount of energy (energy of activation). |
| The minimum energy necessary to cause a reaction to occur is ? | the Energy of Activation. |
| Exothermic or endothermic: energy of products is less than reactants. | Exothermic |
| In a reaction, what is the transition state? | the point at which the activation energy is enough to cause the reaction to occur (the top of the hill). |
| In a reaction, what is an activated complex? | the point at which the activation energy is enough to cause the reaction to occur (the top of the hill). |
| In an exothermic reaction, which side is the heat on, reactant or product? | Product side. A + B ---> C + heat |
| In an endothermic reaction, which side is the heat on, reactant or product? | Reactant side. heat + C ---> A + B |
| At the "activated complex" or "transition state", aka the top of the hill, what is happening? | Reactant bonds are beginning to break and product bonds beginning to form. |
| What four things can you do to speed up a reaction? | 1. raise the temp. 2. increase the concentration. 3. pick better reactants (ionic rather than covalent bonds). 4. add a catalyst. |
| Does a catalyst bond with the reactants? | No. A catalyst increases the rate of a reaction without being consumed. |
| Will a catalyst increase or decrease the energy of activation? | it decreases or lowers the energy of activation. |
| What is a common catalyst used in labs? | Platinum |
| What are the biological molecules that act as catalysts in human bodies called? | enzymes (often protiens) |
| Define "equilibrium". | it is a balance between reactants and products. The amount of product being formed by the forward reaction = the amount being lost by the reverse reaction. |
| true or false: Equilibrium means there are equal amounts or reactants and products. | False. There may not be be equal amounts on both sides. |
| Equilibrium is when all __________ stops? | all spontaneous change stops. |
| State "LeChatelier's Principle". | Any system (reaction) at equilibrium will do whatever it takes to stay at or regain equilibrium. |
| What happens if you change the temperature after an exothermic reaction (system) is at equilibrium? | a) An increase in temp drives it toward the reactants (K gets smaller). b) A decrease drives it toward the products (K gets larger). |
| What happens if you change the temperature after an endothermic reaction (system) is at equilibrium? | a) An increase in temp drives it toward the products (K gets larger). b) A decrease drives it toward the reactants (K gets smaller). |
| What is hypothermia? | Low body temperature due to prolonged exposure to cold. |
| What is normal body temperature in degrees celsius? | 37 degrees celsius. |
| What are the vital signs associated with hypothermia? | Respiratory rate slows. Blood pressure decreases. Heart rate slows. |
| The symptoms of hypothermia due to cold actually happen because ___________? | cellular enzymes become sluggish. |
| When body core temperature reaches 30-32 degrees celsius (87-90 degrees fahrenheit) what happens? | shivering stops, body heat generating capacity is exhausted. |
| When body core temperature reaches 21 degrees celsius (70 degrees F) what happens? | coma results then death due to cardiac arrest. |
| When you induce hypothermia what are you actually doing. | You are slowing down chemical reaction rates in the body. |
| What are some practical uses of hypothermia in medicine? | 1. Chilling body organs for organ transplant. 2. Icing to reduce inflamation from injury. 3. Ice baths for someone with a high fever. |
| How many calories in the "heat of jusion" for water? | 80 calories |
| What is the "heat of fusion"? | The heat energy required to change 1 gram of solid to liquid, or heat lost to freeze a liquid to a solid. |
| How many calories in the "heat of vaporization" for water? | 540 calories |
| What is the "heat of vaporization"? | The heat energy required to change 1 gram of liquid to a gas (steam), or heat loss to condense from a gas to a liquid. |
