Answer:
The answer to your question is 0.35 moles of ZnCl₂
Explanation:
Data
moles of ZnCl₂ = ?
mass of Zn = 23 g
mass of CuCl₂ = excess
Balanced chemical reaction
Zn + CuCl₂ ⇒ ZnCl₂ + Cu
Process
1.- Convert the mass of Zn to moles
-Look for the atomic mass of Zn
Atomic mass = 65.4 g
-Convert the grams to moles
65.4 g -------------- 1 mol
23 g ---------------- x
x = (23 x 1)/65.4
x = 23 / 65.4
x = 0.35 moles of Zn
2.- Calculate the moles of ZnCl₂ using proportions and cross multiplication, and the coefficients of the balanced chemical reaction.
1 mol of Zn ---------------- 1 mol of ZnCl₂
0.35 moles of Zn -------- x
x = (0.35 x 1) / 1
x = 0.35 moles of ZnCl₂
Answer:
Magnesium
Explanation:
When an atom loses are gain the electrons ions are formed.
There are two types of ions.
Anion
Cation
1 = Anion
It is formed when an atom gain the electrons. when atom gain electron negative charge is created on atom. For example.
X + e⁻ → X⁻
2= Cation
It is formed when an atom loses the electrons. when atom lose electron positive charge is created on atom. For example.
X → X⁺ + e⁻
There are seven valance electrons in iodine. To complete the octet it gain one electron and form anion.
Sulfur has six valance electrons it gain two electrons to complete the octet and form anion.
Phosphorus has five valance electrons it gain three electrons two complete the octet and form anion.
Magnesium has two valance electrons it loses two electron to complete the octet and form cation.
Scientists measured a drop in the average global temperature of about 1 degree F (0.6 degrees C).
Answer : The energy removed must be, -67.7 kJ
Solution :
The process involved in this problem are :
The expression used will be:
![\Delta H=[m\times c_{p,g}\times (T_{final}-T_{initial})]+m\times \Delta H_{vap}+[m\times c_{p,l}\times (T_{final}-T_{initial})]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Bm%5Ctimes%20c_%7Bp%2Cg%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D%2Bm%5Ctimes%20%5CDelta%20H_%7Bvap%7D%2B%5Bm%5Ctimes%20c_%7Bp%2Cl%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D)
where,
= heat released by the reaction = ?
m = mass of benzene = 125 g
= specific heat of gaseous benzene = 
= specific heat of liquid benzene = 
= enthalpy change for vaporization = 
Molar mass of benzene = 78.11 g/mole
Now put all the given values in the above expression, we get:
![\Delta H=[125g\times 1.06J/g.K\times (353.0-(425.0))K]+125g\times -434.0J/g+[125g\times 1.73J/g.K\times (335.0-353.0)K]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B125g%5Ctimes%201.06J%2Fg.K%5Ctimes%20%28353.0-%28425.0%29%29K%5D%2B125g%5Ctimes%20-434.0J%2Fg%2B%5B125g%5Ctimes%201.73J%2Fg.K%5Ctimes%20%28335.0-353.0%29K%5D)
Therefore, the energy removed must be, -67.7 kJ
