Finding The Ratio Of Moles Of Reactants In A Chemical Reaction
Tara Keller
Finding the Ratio of Moles of Reactants in a Chemical Reaction
9/6/13
Introduction
The purposes of this lab are to measure the temperature change of the reaction between solutions of sodium hydroxide and phosphoric acid, calculate the enthalpy, H, of neutralization of phosphoric acid, and compare the calculated enthalpy neutralization with the accepted value.
Theory
Calorimetry is the measurement of change of heat in a reaction. A calorimeter is a tool to measure the amount of heat exchange in a chemical reaction (Helmenstine, “Calorimetry”). Calorimetry is used because the knowledge of the amount of energy needed to produce a reaction is extremely useful to scientists studying chemistry. Coffee-cup calorimetry occurs inside of a Styrofoam cup. A known volume of water is poured into the cup and a thermometer is placed through the lid and under the surface of the water. When the chemical reaction occurs in the cup, the heat of the reaction is absorbed by the water. The change in water temperature is then used to calculate the amount heat released or absorbed in the reaction. In this experiment, coffee-cup calorimetry is being used to measure the enthalpy of the reaction between H3PO4 and NaOH.
Apparatus …show more content…
0.60 M phosphoric acid solution- toxic to blood, liver, skin, eyes, bone marrow. Wear goggles and apron (Phosphoric acid MSDS)
1.85 M sodium hydroxide solution- toxic to lungs. Limit exposure (Sodium Hydroxide
Finding the Ratio of Moles of Reactants in a Chemical Reaction
9/6/13
Introduction
The purposes of this lab are to measure the temperature change of the reaction between solutions of sodium hydroxide and phosphoric acid, calculate the enthalpy, H, of neutralization of phosphoric acid, and compare the calculated enthalpy neutralization with the accepted value.
Theory
Calorimetry is the measurement of change of heat in a reaction. A calorimeter is a tool to measure the amount of heat exchange in a chemical reaction (Helmenstine, “Calorimetry”). Calorimetry is used because the knowledge of the amount of energy needed to produce a reaction is extremely useful to scientists studying chemistry. Coffee-cup calorimetry occurs inside of a Styrofoam cup. A known volume of water is poured into the cup and a thermometer is placed through the lid and under the surface of the water. When the chemical reaction occurs in the cup, the heat of the reaction is absorbed by the water. The change in water temperature is then used to calculate the amount heat released or absorbed in the reaction. In this experiment, coffee-cup calorimetry is being used to measure the enthalpy of the reaction between H3PO4 and NaOH.
Apparatus …show more content…
0.60 M phosphoric acid solution- toxic to blood, liver, skin, eyes, bone marrow. Wear goggles and apron (Phosphoric acid MSDS)
1.85 M sodium hydroxide solution- toxic to lungs. Limit exposure (Sodium Hydroxide