Say the dereference between the two is that "Exo" means "outside" and "Endo" means "inside" meaning one pulls heat inside (endothermic) and the other expels heat (exothermic)
The answer is:
2.5 moles
The explanation:
when avogadro's number = 6.02 * 10^23
and when 1 mole of the sample will give → 6.02*10^23 atoms
So, ??? mole of the sample will give→ 1.52 x 10^24 atoms
∴ number of moles = (1.52 X 10^24) * 1 mole / (6.02X10^23)
= 2.5 moles
Answer: 1) endothernic
2) Yes absorbed
Explanation:
Decomposition is a chemical reaction in which one reactant gives two or more than two products. All decomposition reactions are endothermic reactions as energy is absorbed to break the bonds.
Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and 
for the reaction comes out to be positive.
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and for the reaction comes out to be negative.
Answer:
A voltaic cell
Explanation:
A voltaic cell is a device which converts chemical energy to electrical energy. The chemical reactions that take place inside the cell causes electrons to flow from anode to cathode hence, electricity is produced. A simple voltaic cell is made by placing two different metals in contact with an electrolyte separated by a salt bridge. The cathode is the negative electrode while the anode is the positive electrode. It is also called a galvanic cell.
In a voltaic cell having a copper/copper solution half cell, reduction occurs at the cathode. Hence, at the cathode copper II ions accept two electrons and become reduced to ordinary metallic copper. This causes the blue colour of the solution to become discharged (fade) as the cell continues to function.
Answer:
d) a pure substance that can be separated into different elements by chemical means.
Explanation:
Hello,
Sodium chloride (NaCl) is a chemical compound composed by sodium and chlorine. They are chemically bonded through a ionic bond which means that the sodium transfers just one electron (valence electron) to the chlorine to form the bond. Now, if we want to separate them, we must induce a chemical process because bond breaking implies a chemical change, not physical. Thus, a typical way to separate them (break the bond) is via electrolysis in which an electric driving force induce the aforementioned breakdown.
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