The enthalpy change for an exothermic reaction is negative because heat is being released, so that takes out two of the responses. Since energy is being released into the surroundings due to the exothermic reaction, the potential energy of the products is lower than that of the reactants. Energy is being put in to make the reaction occur, but then that energy is all being released into the surroundings thus a lower potential energy level for the products
First, we must find the total mass of CuBr₂:
Mass = 64 + 2 x 80
Mass = 224
Percentage mass of copper = mass of copper x 100 / total mass
Percentage mass of copper = (64 / 224) x 100
Percentage mass of copper = 28.45%
0.0788 will be the number of moles of silver in coin.
<h3><u>How to find the number of moles?</u></h3>
A mole is the mass of a material made up of the same number of fundamental components. Atoms in a 12 gram example are identical to 12C. Depending on the material, the fundamental units may be molecules, atoms, or formula units.
A mole fraction shows how many chemical elements are present. The value of 6.023 x 10²³ is equivalent to one mole of any material (Avagadro's number). It can be used to quantify the chemical reaction's byproducts. The symbol for the unit is mol.
The number of moles formula is denoted by the following expression:
Number of moles = Mass of substance/mass of one mole
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The statement that describes a chain reaction brought about by a nuclear reaction is "neutrons <span>released during a fission reaction cause other nuclei to split." This is applicable to fission reactions only wherein atoms split and produce neutrons that also cause further atoms to split, thus creating a chain or series of reactions.</span>
