6.8 CHAPTER 6. QUANTITATIVE ASPECTS OF CHEMICAL CHANGE
The mass of sodium chloride needed is 0.29 gExercise 6 - 7
- 5.95 g of potassiumbromide was dissolved in 400 cm^3 of water. Calculate its molarity.
- 100 g of sodium chloride (NaCl) is dissolvedin 450 cm^3 of water.
(a) How many moles ofNaCl are present in solution?
(b) What is the volumeof water (in dm^3 )?
(c) Calculate the concentration of the solution.
(d) What mass of sodium chloride would needto be added for the concentration to become
5.7 mol.dm−^3?- What is the molarityof the solution formed by dissolving 80 g of sodium hydroxide (NaOH)in
500 cm^3 of water? - What mass (g) of hydrogen chloride (HCl) is needed to make up 1000 cm^3 of a solution of
concentration 1 mol.dm−^3? - How many moles ofH 2 SO 4 are there in 250 cm^3 of a 0.8M sulphuric acidsolution? What mass
of acid is in this solution?
More practice video solutions or help at http://www.everythingscience.co.za(1.) 00yz (2.) 00z0 (3.) 00z1 (4.) 00z2 (5.) 00z36.8 Stoichiometric calculations ESBBN
Stoichiometry is the calculation of the quantitiesof reactants and products in chemical reactions. It is
also the numerical relationship between reactants and products. In grade 10 you learnt how towrite
balanced chemical equations. By knowing the ratios of substances in areaction, it is possible touse
stoichiometry to calculate the amount of eitherreactants or products that are involved in the reaction.
The examples shown below will make this concept clearer.
See video: VPjgn at http://www.everythingscience.co.za