To a solution consisting of 45 g of water and 15 g of salt, 65 g of water and 10 g of the same salt were added. Calculate the mass fraction of salt in the resulting solution.
ω = m (substance) / m (solution)
Find the mass of the substance m = 15 + 10 = 25 g
Find the mass of the solution m = 45 + 15 + 65 + 10 = 135 g
ω = 25 * 100/135 = 18.5%
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.