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Explain why potassium is more reactive than sodium, giving the balanced chemical symbol equation for the reaction of potassium and water.

K + H₂O --> KOH + H₂Both potassium and sodium possess one electron in their outer shell. Both elements readily give up this unpaired electron and so for this reason are considere...

Answered by Liam F. • Chemistry tutor

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Given the following equilibrium: H2O + H2O <-> H3O+ + OH- and the Kw = 10^-14, determine the concentration of OH- species after the addition of 1 mmol of HCl to 1 L of neutral water.

As HCl is a strong acid, it will fully dissociate in water, releasing 1 mmol of H⁺, which will be the final concentration of protons in solution. The autoprotolysis equilibrium of water (or K

Answered by Samuel N. • Chemistry tutor

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The reversible reaction of sulfur dioxide and oxygen to form sulfur trioxide is shown below. 2SO2(g) + O2(g) 2SO3(g) An equilibrium mixture contains 2.4mol SO2, 1.2mol O2 and 0.4mol SO3. The total pressure is 250atm. What is the p(SO3)?

First step is to calculate the mole fraction of the SO3. This can be done by dividing the moles of SO3 by the total moles at equilibrium to give 0.4/4. This is then multiplied by the total pressure at equ...

Answered by Saji M. • Chemistry tutor

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Calculate the concentration in mol/dm3 of 8.0 g of sodium hydroxide (NaOH) in solution with a volume of 50 cm3. (Note Ar(Na) = 23, Ar(O) = 16, Ar(H) = 1)

Calculate Mr(NaOH): Mr(NaOH) = 23 + 16 + 1 = 40, Calculate NaOH moles: n= m/Mr, n= 8.0/40, n= 0.2 moles, Calculate NaOH concentration:(converting from cm³ to dm³ by /1000) c= n/v, c=...

Answered by Imogen C. • Chemistry tutor

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Define three element properties and explain how they change across the periodic table.

First, we have atomic and ionic radii which, as the name suggests, refer to the size of the atom, or the ion in the latter case. Radii increase as you go down a group (i.e. Halogens), since the number of ...

Answered by Danai Athina I. • Chemistry tutor

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