Question

please answer these questions

1-Consider the following balanced equation:

2 Fe(s) + 3 Cl₂(g) → 2 FeCl₃(s)

How many moles of iron(III) chloride are obtained when 7.67 moles of chlorine gas react with excess solid iron? Assume the reaction is 100% efficient.

2- What mass of hydrochloric acid must have reacted with magnesium if 9.56 grams of hydrogen were produced? Include units with your answer.

The UNBALANCED equation is provided:

Mg(s) + HCl(aq) → H₂(g) + MgCl₂(aq)

3- What volume (in L) of 0.249 M AgNO₃ is required to react exactly with 289 mL of 0.656 M K₂SO₄ solution? Hint: be sure to write the balanced equation!

4- Calculate the molarity of a solution containing 72.6 mol of ethanol (CH3CH2OH) in 16.68 L of solutio

5-If you have 8,817,000,000 platinum atoms, how many moles do you have?

Answer 1

Ans 1 :

3 moles of chlorine gas gives 2 moles of FeCl3

So 7.67 moles of chlorine gas will give : (7.67 x 2) / 3

= 5.11 mol of iron (III) chloride.

Ans 2 :

The balanced reaction is given as :

Mg + 2HCl = MgCl2 + H2

Number of mol of hydrogen = 9.56 / 2.01588 = 4.74 mol

So number of mol of HCl used will be: 2 x 4.74 mol = 9.48 mol

Mass of HCl used = 9.48 x 36.46

= 345.8 g

Ans 3 :

The balanced equation is given as :

2AgNO3 + K2SO4 = Ag2SO4 + 2KNO3

Using the formula , M1V1 / n1 = M2V2 / n2

where M is molarity , V is volume and n is number of mol

= (0.656 x 289) = (0.249 x V) / 2

= 379.168 = 0.249 x V

V = 1522.8 mL

or 1.5 L

Ans 4 :

Molarity = no. of mol of solute / volume of solution in L

M = 72.6 / 16.68

= 4.35 M

Ans 5 :

1 mole of substance has 6.022 x 10²³ atoms

So number of moles of platinum = 8,817,000,000 / (6.022 x 10²³)

= 1.46 x 10^-14 mol