Kinetic molecular theory and states of matter
States of Matter There are three different states of matter: solids, liquids and gases. These three states of matter behave differently in space: Solids have got a both a fixed…
Moles VIII – Redox Titrations
Question 1 Balance the following equations in acidic conditions: As2O3+ NO3- à H3AsO4 + N2O3 MnO4- + S2O32- à Mn2++ SO42- H2O2+ Cr2O72¯ àCr3+ + O2 + H2O IO3- + SO2 à I2…
Moles VII – Back Titrations
Question 1 Some pure magnesium carbonate was added to 145. mL of 1.00 M HCl. When the reaction had finished, the solution was acidic. 25.0 mL of 0.500 M Na2CO3 solution…
Moles VI – Titrations
Question 1 A solution of sodium hydroxide contained 0.250 mol dm-3. Using phenolphthalein indicator, titration of 25.0 cm3 of this solution required 22.5 cm3 of a hydrochloric acid solution for complete neutralisation.…
Moles V – Gas Laws
Question 1 Calculate the volume occupied by one mole of a gas at 25 oC and 100 kPa. Question 2 Calculate the pressure of a gas given that…
Moles IV – Concentrations
Question 1 Calculate the number of moles of H2SO4 in 50 cm3 of a 0.50 moldm-3 solution. Question 2 Calculate the number of moles of FeSO4 in 25 cm3…
Moles III – Empirical Formulae
Question 1 What is the empirical formula of a compound containing 60.0% sulfur and 40.0% oxygen by mass? Question 2 A compound is found to contain 23.3% magnesium, 30.7% sulfur,…
Moles II – Stoichiometry
Question 1 Given the chemical equation Na(s) + H2O(ℓ) → NaOH(aq) + H2(g) a) Balance the equation. b) How many molecules of H2are produced when 332 atoms of Na react? Question 2…
Moles I – Introduction
Question 1 How many atoms are present in 4.55 mol of Fe? How many atoms are present in 0.0665 mol of K? How many molecules are present in 2.509 mol…