Answer:
The answer to your question is: Excess oxygen = 2.3 mol
Explanation:
Data
ZnS = 5 mol
O2 = 9.8 mol
Excess reactant = ?
Balanced reaction
2ZnS(s) + 3O2(g) → 2ZnO(s) + 2SO2(g)
MW ZnS = 65 + 32 = 97 x 2 = 194 g
MW O2 = 16 x 6 = 96 g
2 mol of ZnS ------------------- 3 mol O2
Ratio from the reaction = 3 mol O2/ 2 mol ZnS
= 1.5
Ratio from the quantities in the experiment = 9.8 mol O2 / 5 mol of ZnS
= 1.96
Excess reactant = Oxygen because the ratio increases
2 mol of ZnS ------------------- 3 mol O2
5 mol of ZnS ------------------- x
x = (5 x 3) / 2
x = 7.5 mol of O2
Excess Oxygen = 9.8 mol - 7.5 mol
Excess oxygen = 2.3 mol
Answer:
4
Explanation:
Avogadro’s number represent the number of the constituent particles which are present in one mole of the substance. It is named after scientist Amedeo Avogadro and is denoted by .
Also, it is the number of particles in exactly 12.000 g of isotope carbon 12.
Avogadro constant:-
Hence,
Mass of = 131.293+ n18.998 g
So,
molecules have a mass of 131.293+ n18.998 g
Also,
molecules have a mass of g
So,
molecules have a mass of g
Also, given mass = 0.172 g
Thus,
<u>Thus, value of n is 4.</u>
D. The energy released or absorbed during the reaction
Mg + 2HCl = H₂ + MgCl₂
n(HCl)=c(HCl)v(HCl)
n(H₂)=n(HCl)/2=c(HCl)v(HCl)/2
n(H₂)=3.0mol/L*0.2500L/2=0.375 mol≈0.38 mol
Gaseous compound X is an oxidising agent. X is bubbled through separate solutions of aqueous
potassium iodide and acidified potassium manganate(VII).
Х
Х
aqueous
potassium iodide
acidified potassium
manganate(VII)
Which row shows the colour changes when X is bubbled through these two solutions?
aqueous
potassium iodide
acidified potassium
manganate(VII)
A
brown to colourless
B
brown to colourless
no change
purple to colourless
no change
с
colourless to brown
D