Chemistry - Quantitative 0.0 / 5 ? ChemistryCalculations, moles and yieldGCSEAQA Created by: LunaShomeiRoseCreated on: 16-10-18 18:52 What's relative atomic mass? (of an isotope) - Ar Avarge mass of an elements isotopes,taking into account how common each isotope is (abundance) 1 of 11 What is relative formula mass? (of a compound) - Mr Sum of relative atomic mass of each element in compound 2 of 11 The law of conservation of mass is that no ___ are lost/gained in reaction so p___ mass = r___ mass No atoms are lost/gained so product mass = reactant mass 3 of 11 With this is mind, what would the product weigh if Mg (weight: 24g) reacted with Cl2 (weight: 71g)? MgCl2 = 24 + 71 = 95g 4 of 11 How many grams of an element is one mole? The atomic number. E.g. Carbon has atomic number of 12. So 12g is 1 mol of that element. 5 of 11 How do you calculate number of moles? Mass/Ar (relative atomic number) [total weight/weight of one of those elements] 6 of 11 How many mols are in 48g of Mg (Ar=12) 48/24 = 4 moles 7 of 11 How do you calculate concentration of a solution? concentration = mass/volume 8 of 11 200g of a chemical is dissolved in water to volume of 1 dm3. Calculate concentration. 200g/1 = 200g/dm3 9 of 11 Calculate mass of chemical needed to dissolve to volume 0.4 dm3 to give concentration of 600g/dm3 mass = concentration x volume. 600 x 0.4 = 240 10 of 11 How do you calculate percentage concentration of mass? (element mass/compound mass) x 100 11 of 11
Comments
No comments have yet been made