A double replacement is when the reactants switch with their opposite charge. For example, AB + CD = AD + BC.
In this case the given is K2SO4 + Pb(NO3)2 = ____ + ____
The answers is PbSO4 and KNO3 would expect the products of this reaction.
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:
-431.5 J/g
Explanation:
Mass of solution = Mass of solute + mass of solvent
Solute is KOH while solvent is water.
Mass of KOH = 16.9 g
Mass of water = 90.8 g
Mass of solution = 16.9 + 90.8
= 107.7 g
Change in temperature (Δt) = 34.27 - 18.5
= 16.2 °C
Heat required to raise the temperature of water is released by dissolving KOH.
Therefore,
Heat released by KOH = m × s× Δt
= 107.7 × 4.18 × 16.2
= 7293 J
Heat released by per g KOH = 7293 J/16.9 g
= 431.5 J/g
As heat is released therefore, enthalpy change would be negative.
Enthalpy change of KOH = -431.5 J/g
Shining bright blue light on a strip of metal is the answer
Answer:
Sodium chloride has a crystalline face-centered cubic structure whereas metallic sodium body-centered cubic structure.
Explanation:
Hello, atomic arrangements provide the molecules different features and behaviors, since the sodium metal has a body-centered cubic structure (https://en.wikipedia.org/wiki/Cubic_crystal_system#/media/File:Cubic-body-centered.svg) the lack of inner atoms, allows the material to be soft and bendable. On the other hand the compacted sodium chloride's face-centered cubic structure (https://en.wikipedia.org/wiki/Cubic_crystal_system#/media/File:Cubic-face-centered.svg), provides it a crystalline structure which is hard and brittle since the atoms are closer.
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