Answer:
The answer is B on edge
Explanation:
Here are my notes on this section for anyone that needs them
Enthalpy and State Function
Bonds contain potential energy. Breaking and forming bonds involves energy. Reactants and products contain energy. Enthalpy (H) is a measure of heat and internal energy in a system.
A state function is a quantity whose change in magnitude during a process depends only on the beginning and end points the process, not the path taken between them. Enthalpy change during reaction depends only on the identity of reactants and products and their initial and finial condition
Enthalpy of Formation
enthalpy of formation (Hf) is the energy absorbed or released when a pure substance forms from elements in their standard states
Units: kJ/mol, kcal/mol
Standard state is the natural state of an element at 1 atm (atmosphere of pressure) and 25 degrees celsius. Hf for a pure element in its standard state is 0 kJ/mol.
H (hydrogen): H2(g)
N (nitrogen): N2(g)
O (oxygen): O2(g)
F (fluorine): F2(g)
Cl (chlorine): Cl2(g)
Br (bromine): Br2(l)
Hg (mercury): Hg(l)
Enthalpy of Reaction
Enthalpy of reaction (Hrxn) is energy absorbed or released during a chemical reaction
Hrxn negative: exothermic reaction
Hrxn positive: endothermic reaction
Hess's Law: Hrxn = Σ(ΔHƒ, products) − Σ(ΔHƒ, reactants)
thermochemical equation: the chemical equation that shows the state of each substance involved and the energy change involved in a reaction
Find the kJ/mol of the product and then subtract the kJ/mol of the reactants.
Answer:
You got it right
Explanation:
Im am pretty sur because the gravatational pull- You know what imma make this to compliated LOL
We want to take inventory of the right and left side
Right: S=1 O = 2 Li = 2 Se= 1
Left: S= 1 Se=2 Li= 2 O=1
Lets balance out each side because we see we are off by 1 oxygen on the left
Add a coefficient of 2 on the Li2O
Add a coefficient of 2 on the right Li2Se
Now we have So2+ 2Li2Se ---> SSe2+ 2Li2O
or
The equation is already balanced, assuming that there is supposed to be a yields symbol between 2Li2Se and SSe2.
To find out whether or not this equation is balanced, make a little T-chart with the left side of the equation on one side and the left on the other. Next to each element, write down the amount they start off with and make changes as you add coefficients.
Hope this helps!
The question is incomplete, the complete question is;
Rico is doing an experiment. He makes a solution of calcium carbonate in a beaker of 200 mL of water at room temperature (25 °C). He adds a small amount of lemon juice to the solution and a chemical reaction begins. Rico reduces the temperature of the solution by 10 °C by adding ice. As the solution cools, what will happen to the chemical reaction?
A. The chemical reaction will stop suddenly.
B. There will be no change in the rate of the chemical reaction.
C. The chemical reaction will slow as the water cools.
D. The speed of the chemical reaction will increase as the water cools.
Answer:
C. The chemical reaction will slow as the water cools.
Explanation:
The rate of a chemical reaction is dependent on the temperature of the reaction system. This derives directly from the collision theory of chemical reaction.
The higher the temperature of the system, the more frequently the particles collide and the faster the rate of reaction.
As the temperature is decreased, the rate of reaction decreases simultaneously. Therefore, as Rico decreases the temperature from 25 degrees to 10 degrees, the rate of reaction decreases accordingly.