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Help with chemistry questions.

a) If the mass of iron is 98.0g, what is the maximum mass of iron oxide that can be produced from this reaction

2Fe + 1.5 O^2 —> Fe^2 O^3

b) If 22.6cm^3 of 0.5 mol dm^-^3 NaOH solution was required to neutralise 25.0cm^3 of HCl solution, what is the concentration of the HCl solution?

c) If 34.6cm^3 of 1.5mol dm^-^3 NaOH solution was required to neutralise 25.0cm^3 of H^2 SO^4 solution, what is the concentration of the H^2 SO^4 solution?


what’re the formulas to work these out? thanks.
a.) You're given the chemical equation, so work out no. of moles of iron then use mole ratio to find no. of moles of iron(III)oxide. Then calculate the Molar mass and workout the mass.
b.) NaOH + HCl -----> NaCl +H₂O . You can work out no. of moles of sodium hydroxide then proceed to working out the conc. of HCl.
c.) 2NaOH + H₂SO₄ ------> Na₂SO₄+ 2H₂O. Work out no. of moles of sodium hydroxide then proceed to working out the conc. of H₂SO₄.

You may find these formulae useful:
moles=mass/molar mass
moles=concentration x volume
Converting from cm³ to dm³ divide by 1000
can i help you with it
Original post by Mr.noname
a.) You're given the chemical equation, so work out no. of moles of iron then use mole ratio to find no. of moles of iron(III)oxide. Then calculate the Molar mass and workout the mass.
b.) NaOH + HCl -----> NaCl +H₂O . You can work out no. of moles of sodium hydroxide then proceed to working out the conc. of HCl.
c.) 2NaOH + H₂SO₄ ------> Na₂SO₄+ 2H₂O. Work out no. of moles of sodium hydroxide then proceed to working out the conc. of H₂SO₄.

You may find these formulae useful:
moles=mass/molar mass
moles=concentration x volume
Converting from cm³ to dm³ divide by 1000
Original post by Assignment Pro
can i help you with it


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