The concentration of a solution can be calculated using the equation concentration of solution = mass of solid / volume of solution A student dissolved 9.25g of ammonium chloride in water and made up the solution to a volume of 200 cm³ - Edexcel - GCSE Chemistry - Question 2 - 2021 - Paper 1

To find the concentration of the solution, we will use the formula:

ext{concentration of solution} = rac{ ext{mass of solid}}{ ext{volume of solution}}

1. Convert the volume from cm³ to dm³:

   • Since 1 dm³ is equal to 1000 cm³,
   • We convert 200 cm³ to dm³:
   ext{Volume in dm³} = rac{200 ext{ cm}^3}{1000} = 0.2 ext{ dm}^3

2. Substitute the values into the equation:

   • Mass of solid = 9.25 g
   • Volume of solution = 0.2 dm³
   ext{concentration} = rac{9.25 ext{ g}}{0.2 ext{ dm}^3} = 46.25 ext{ g dm}^{-3}

3. Final answer:

   • The concentration of the solution is 46.25 g dm⁻³.