C—stems and leaves growing upward?
A. Potassium oxide
B. Calcium chloride
C. Magnesium nitride
D. Sodium hypochlorite
E. Potassium nitrate
Zn+2HCl ----> 2ZnCl2 + H2
For 2.50 g of Zn
Mass per mol = 2.50/molar mass of Zn = 2.50/65.38 = 0.0382 g/mol
There are two moles of ZnCl2 and total mass = 2*0.0382*molar mass of ZnCl2 = 2*0.0382*136.286 = 10.42 g
For 2 g of HCl
Mass per mol = 2/2*molar mass of HCl = 2/ (2*36.46) = 0.0274 g/mol
For the two moles of ZnCl2, mass produced = 2*0.0274*136.286 = 7.48 g
It can be noted that 2 g of HCl produced less amount of ZnCl and thus it is the limiting reagent.
The concentration of OH⁻ is first converted to pOH bu using followinf formula,
pOH = -log [OH⁻]
Putting value,
pOH = -log (0.006)
pOH = 2.221
As we know,
pH + pOH = 14
Solving for pH,
pH = 14 - pOH
Putting value of pOH,
pH = 14 - 2.221
pH = 11.779
Result:
Option-1 is the correct answer.
