These energy exchange are not change in kinetic energy. They are changes is bonding energy between the molecules. If heat is coming into a substance during a phase change, then this energy is used to by break the bounds between the molecules of the substance. The example we will use here is ice melting into water.
Nacl = (. 23+35. 5)
= 58.5g
.
1 mol of Nacl = 58.5g
X mol Of Nacl = 25g
X Mol of Na Cl =25 ÷ 58.5
X mol of Nacl = 0.4 mol
A. Cesium because reactivity of alkali metals increases from the top to the bottom of the group.
Answer:
the answer is c
Explanation:
a chemical change mean it changes it for ever and a physical change mean it can be changed back and evaporation means it turns solid water in to gas hope this helps
Answer:
C = Electrons are won and lost.
Explanation:
The oxidation reduction reactions are called redox reaction. These reactions are take place by gaining and losing the electrons and oxidation state of elements are changed.
Oxidation:
Oxidation involve the removal of electrons and oxidation state of atom of an element is increased.
Reduction:
Reduction involve the gain of electron and oxidation number is decreased.
Consider the following reactions.
4KI + 2CuCl₂ → 2CuI + I₂ + 4KCl
the oxidation state of copper is changed from +2 to +1 so copper get reduced.
CO + H₂O → CO₂ + H₂
the oxidation state of carbon is +2 on reactant side and on product side it becomes +4 so carbon get oxidized.
Na₂CO₃ + H₃PO₄ → Na₂HPO₄ + CO₂ + H₂O
The oxidation state of carbon on reactant side is +4. while on product side is also +4 so it neither oxidized nor reduced.
H₂S + 2NaOH → Na₂S + 2H₂O
The oxidation sate of sulfur is -2 on reactant side and in product side it is also -2 so it neither oxidized nor reduced.
Oxidizing agents:
Oxidizing agents oxidize the other elements and itself gets reduced.
Reducing agents:
Reducing agents reduced the other element are it self gets oxidized.
