Answer: The concentration of excess ![[OH^-]](https://tex.z-dn.net/?f=%5BOH%5E-%5D)
in solution is 0.017 M.
Explanation:
1. 
moles of 
1 mole of 
give = 1 mole of 
Thus 0.019 moles of give = 0.019 mole of
2. moles of 
According to stoichiometry:
1 mole of 
gives = 2 moles of 
Thus 0.012 moles of give = 
moles of
As 1 mole of neutralize 1 mole of
0.019 mole of will neutralize 0.019 mole of
Thus (0.024-0.019)= 0.005 moles of will be left.
![[OH^-]=\frac{\text {moles left}}{\text {Total volume in L}}=\frac{0.005}{0.3L}=0.017M](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D%5Cfrac%7B%5Ctext%20%7Bmoles%20left%7D%7D%7B%5Ctext%20%7BTotal%20volume%20in%20L%7D%7D%3D%5Cfrac%7B0.005%7D%7B0.3L%7D%3D0.017M)
Thus molarity of in solution is 0.017 M.
Answer:
A. 
Explanation:
The work function of the Platinum = 
For maximum wavelength, the light must have energy equal to the work function. So,
Where,
h is Plank's constant having value 
c is the speed of light having value 
is the wavelength of the light being bombarded
Thus,
to the proper number of significant figures) to the following? (12.67+19.2)(3.99)/(1.36+ 11.366).
First convert grams to moles:
70.0g *(mole/98.079) = 0.7137mole
Remember that molarity is moles per liter:
0.7137mole *(1/280mL) *(1000mL/L) = 25.5M
Answer:
Pb(NO3)2
Cd(NO3)2
Na2SO4
Explanation:
In the first part, addition of HCl leads to the formation of PbCl2 which is poorly soluble in water. This is the first precipitate that is filtered off.
When the pH is adjusted to 1 and H2S is bubbled in, CdS is formed. This is the second precipitate that is filtered off.
After this precipitate has been filtered off and the pH is adjusted to 8, addition of H2S and (NH4)2HPO4 does not lead to the formation of any other precipitate.
The yellow flame colour indicates the presence of Na^+ which must come from the presence of Na2SO4.
