Answer:
0.20 mol
Explanation:
Let's consider the reduction of iron from an aqueous solution of iron (II).
Fe²⁺ + 2 e⁻ ⇒ Fe
The molar mass of Fe is 55.85 g/mol. The moles corresponding to 5.6 g of Fe are:
5.6 g × 1 mol/55.85 g = 0.10 mol
2 moles of electrons are required to deposit 1 mole of Fe. The moles of electrons required to deposit 0.10 moles of Fe are
0.10 mol Fe × 2 mol e⁻/1 mol Fe = 0.20 mol e⁻
Answer:
The new pressure is 44.4 kPa.
Explanation:
We have,
Initial volume, 
Initial pressure, 
It is required to find the new pressure when the volume is increased to 50 ml. The relationship between pressure and volume is known as Boyle's law.

is final pressure

So, new pressure is 44.4 kPa.
<h2>Step 1 : Identify the given </h2>
Volume = 250mL
Density = 1.19 g/ML
<h2>Step 2 . Calculate the mass of HCL </h2>
Density = mass/volume
∴Mass = Density * Volume
= 1.19g/mL* 250mL
= 297,5g
<h2>Step 3 : Calculate the total mass of the solution, given that concentration HCL is 38% </h2>
Mass of the total solution can be calculated by the following :
38% = Mc /297.5 * 100
Mc = 38/100 *297.5
= 113.05grams
• Finally, this means that mass of the total solution of 0.125M HCL i,s 113grams, ,you would use this mass to prepare 250 mL of 0.125 M HCl from concentrated HCl (aq) that is 38.0%