Answer:
1) Fe³⁺
2) Al³⁺
3) Pb²⁺
Explanation:
Because all of the metal ion concentrations are the same, the order that they precipitate will be dependent on the 
values of each individual precipitate. The lower the , the less OH⁻ needed in solution to precipitate.
The three values are
= 2.6 x 10⁻³⁹ for Fe(OH)₃,
= 1.9 x 10⁻³³ for Al(OH)₃
= 1.4 x 10⁻¹⁵ for Pb(OH)₂
This means that the ions will precipitate in the following order Fe³⁺ then Al³⁺ then Pb²⁺
Note: if too much OH⁻ is added Al³⁺ will redissolve into solution because of the formation of the soluble complex Al(OH)⁻₄ (
= 1.1 x 10³³)
A hydronium ion has a charge of one plus
Answer:
16.86%
Explanation:
Na3N is sodium nitride.
% of N = mass of N/ molar mass of Na3N *100
% of N = 14/83*100= 16.86%
Answer:
91.7 kJ
Explanation:
Step 1: Given data
- Mass of ammonia (m): 66.7 g
- Molar heat of vaporization of ammonia (ΔH°vap): 23.4 kJ/mol
Step 2: Calculate the moles (n) corresponding to 66.7 g of ammonia
The molar mass of ammonia is 17.03 g/mol.
66.7 g × 1 mol/17.03 g = 3.92 mol
Step 3: Calculate the heat (Q) required to boil 3.92 moles of ammonia
We will use the following expression.
Q = ΔH°vap × n
Q = 23.4 kJ/mol × 3.92 mol = 91.7 kJ
Answer:- 0.00724 moles.
Solution:- Grams of salicylic acid are given and it asks to calculate the moles.
For the moles, we divide the grams by the molar mass.
Formula of salicylic acid is 
Molar mass = 7(12.01)+6(1.01)+3(16.00)
= 84.07+6.06+48.00
= 138.13 gram per mol
We could make the dimensional analysis set up for showing unit cancellation and have the moles.
= 0.00724 moles
So, there will be 0.00724 moles of salicylic acid in it's 1.00 gram.
