0
The enthalpy of formation (deltaHf) is the enthalpy change when 1 mole of a compound is formed from its constituent elements in their standard states. The deltaH of a reaction is the difference in enthalpy between the products and the reactants. The deltaH of a reaction can be calculated by taking the sum of the deltaHf of the products minus the sum of the deltaHf of the reactants.
What else can I help you with?
What is the name of the chemical reaction when energy is absorbed from the outside?
Endothermic reaction. See Related Link.
Is a double displacement reaction hydrogen bonding?
The double displacement reaction is not related to hydrogen bonding.
Can you reverse an iron nail rusting?
NO!!!! There is a phycial chemical equation named the 'Gibbs Free Energy Change'. If the calculations result in a negative answer then the reaction is feasible, but the reverse (positive answer) is NOT feasible. DeltaG = DeltaH - T*DeltaS is the basic equation. DeltaH is the enthalpy change (kJmol^(-1) DeltaS is the entropy change (J mol^(-1)(K^(-1)) Careful with these units and their conversion. T is the temperature in (Kelvin(K)). So without putting in any numbers, for the rusting of iron 'DeltaG is negative(-). However, to try and make the reaction go the otherway , then DeltaG is positive(+), and so is NOT feasible.
How is enthalpy related to the spontaneously of a reaction?
H < 0 contributes to spontaneity.
What factor in reaction rate is related to the amount of reactants?
This is the concentration of reactants.
What is a chemical reaction at equilibrium?
deltaG = deltaH -TdeltaS. deltaG = 0 at equilibrium. Therefore deltaH = TdeltaS
What does a negative deltaH tell about a reaction?
the reaction is exothermic
Is baking soda and citric acid a endothermic or exothermic reaction?
It is endothermic. The heat of the water in the calorimeter decreases (giving you a -deltaH), which means that the system absorbed heat, making the reaction endothermic.
Which of the following is endothermic a dry ice evaporating b a sparkler burning c the reaction that occurs in a chemical cold pack often used to ice athletic injuries?
Dry ice evaporating is endothermic-->+DeltaH A sparkler burning is exothermic--->-DeltaH The reaction that occurs in a chemical cold pack often used to ice athletic injuries is endothermic--->+DeltaH
The reaction between strontium metal and chlorine gas is described by the following thermochemical equation Sr s Cl2 g plus SrCl2 s deltaH -829 kJ mol-1 What will be the enthalpy change to 2 sig figs?
-830
How can an unknown deltaH reaction be determined using Hess's law?
By manipulating known reactions with known enthalpy changes to create a series of intermediate reactions that eventually add up to the desired reaction whose enthalpy change is unknown. By applying Hess's law, the sum of the enthalpy changes for the intermediate reactions will equal the enthalpy change of the desired reaction, allowing you to determine its enthalpy change.
What is the balanced chemical equation Nabh4 plus h20 yield NaBo plus h2?
NaBH4 + 2H2O -> NaBO2 + 4H2 [1] DeltaG(298K)= -299 kJ/mol BH4 DeltaH(298K)= -231 kJ/mol BH4 (10.8 mass% H) NaBH4 + 4H2O -> NaB(OH)4 + 4H2 [2] DeltaG (298K)= -315 kJ/mol BH4 DeltaH = -247 kJ/mol BH4 (7.28 mass% H) NaBH4 + 6H2O -> NaB(OH)4.2H2O [3] DeltaG = -319kJ/mol BH4 DeltaH = -213 kJ/mol BH4 (5.48 mass% H) *Hydrolysis in Eq.[1] is not the most favorable reaction!
What is the name of the chemical reaction when energy is absorbed from the outside?
Endothermic reaction. See Related Link.
How are temperature and the Arrhenius theory related?
The reaction rate of a chemical reaction is dependent on temperature.
Is a double displacement reaction hydrogen bonding?
The double displacement reaction is not related to hydrogen bonding.
When the actual free energy change of a reaction change in G has a numerical value of less than zero negative number what will happen?
When the delta G is negative the reaction is said to be spontaneous or in other words favorable. It also means the reaction is irreversible once full product concentration is reached. If delta G is positive, the reaction is unfavorable thus can easily be reversed. If it is zero it is at equilibrium.
How is the speed of chemical reaction related to the spontaneity of the reaction?
The speed of a given chemical reaction is directly responsible for spontaneity of the reaction. The reaction force and effect is contingent upon the speed of the reaction. The faster the reaction, the more force will be produced.
