Concentration and gas volumesIB MYP Chemistry: Flashcards
What these 12 flashcards ask
- What is the formula for concentration in g dm⁻³?
- How do you convert cm³ to dm³?
- What is 250 cm³ in dm³?
- What is the formula linking moles, concentration and volume?
- How do you calculate moles from mass?
- How do you convert mol dm⁻³ to g dm⁻³?
- What is the volume of one mole of any gas at room temperature and pressure?
- How do you find the volume of a gas from its moles at rtp?
- How many cm³ are in 0.60 dm³?
- What is a titre?
- What is the end point of a titration?
- In a 1 : 1 titration, how do the moles of the two reactants compare?
Exam questions on Concentration and gas volumes
- A pharmacist in Lagos prepares a saline solution for a clinic by dissolving 4.5 g of sodium chloride in water and making the solution up to 500 cm³.The pharmacist needs 250 cm³ of this solution for a patient. Calculate the mass of sodium chloride in 250 cm³ of the solution.2 marks
- A student in Singapore reacts magnesium ribbon with excess dilute hydrochloric acid at room temperature and pressure. The equation is Mg + 2HCl → MgCl₂ + H₂. At room temperature and pressure, one mole of any gas occupies 24 dm³. The relative atomic mass of magnesium is 24.Calculate the volume of hydrogen, in cm³, produced when all of the 0.60 g of magnesium reacts.2 marks
- A quality-control chemist at a food factory in Seville checks the concentration of a sodium hydroxide cleaning solution by titration. She measures 25.0 cm³ of the cleaning solution into a conical flask and adds hydrochloric acid of concentration 0.100 mol dm⁻³ from a burette until the indicator changes colour. The mean titre is 20.0 cm³. The equation is NaOH + HCl → NaCl + H₂O.Calculate the number of moles of hydrochloric acid used in the titration.3 marks
Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).