<u>Answer:</u> The mass of iron in the ore is 10.9 g
<u>Explanation:</u>
We are given:
Mass of iron (III) oxide = 15.6 g
We know that:
Molar mass of Iron (III) oxide = 159.69 g/mol
Molar mass of iron atom = 55.85 g/mol
As, all the iron in the ore is converted to iron (III) oxide. So, the mass of iron in iron (III) oxide will be equal to the mass of iron present in the ore.
To calculate the mass of iron in given mass of iron (III) oxide, we apply unitary method:
In 159.69 g of iron (III) oxide, mass of iron present is
So, in 15.6 g of iron (III) oxide, mass of iron present will be =
Hence, the mass of iron in the ore is 10.9 g
Answer:
<em>The weakest conjugate is HClO-.</em>
Explanation:
As a general rule, the stronger the Bronsted-Lowry acid, the weaker its conjugate base, and vice versa.
Acid 1: HClO is a strong acid, hence its conjugate base would be weak
Acid 2: H3PO4 is a weak acid, hence its conjugate base would be strong
Acid 3: hydrogen sulphide is also a moderately weak acid with a moderately strong conjugate base.
In order of increasing strengths:
HClO < H2S < H3PO4
Answer:
0.0036 moles of NaOH are present
Explanation:
A solution of 0.1mol/dm³ contains 0.1 moles of solute (In this case, NaOH), per 1 dm³ of solution.
36cm³ are in dm³ (1000cm³ / 1dm³):
36cm³ * (1dm³/1000cm³) = 0.036dm³
The moles are:
0.036dm³ * (0.1mol/dm³) = 0.0036 moles of NaOH are present
NaOH+ HCl--> NaCl+ H2O
From this balanced equation, we know that 1 mol NaOH= 1 mol HCl (keep in mind this because it will be used later).
We also know that 0.15 M HCl aqueous solution (soln)= 0.15 mol HCl/ 1 L of HCl soln (this one is based on the definition of molarity).
First, we should find the mole of HCl:
16.0 mL HCl soln* (1 L HCl soln/ 1,000 mL soln)* (0.15 mol HCl/ 1L HCl soln)= 2.40* 10^(-3) mol HCl.
Now, let's find the concentration of NaOH aqueous soln:
2.40* 10^(-3) mol HCl* (1 mol NaOH/ 1 mol HCl)* (1/ 12.0 mL NaOH soln)* (1,000 mL NaOH soln/ 1L NaOH soln)= 0.20 M NaOH aqueous soln.
The final answer is (2) 0.20 M NaOH (aq).
Also, this problem can also be done by using dimensional analysis. Don't forget significant figures.
Hope this would help~