Смесь нитратов серебра и магния прокалили. полученную в результате реакции смесь газов массой 46,4 г охладили и обработали 200 мл воды. В результате реакции при этом осталось 2,24 л малорастворимого в воде газа. Рассчитайте массовые доли нитрата серебра и нитрата магния в исходной смеси и массовую долю вещества в образовавшемся растворе
To solve this problem, we need to use the principles of stoichiometry to calculate the mass fractions of silver nitrate and magnesium nitrate in the original mixture and the mass fraction of the resulting solution. First, let us calculate the number of moles of the gas that remained after the reaction. Using the ideal gas law, PV=nRT, where P is the pressure (which can be assumed to be 1 atm), V is the volume (which is given as 2.24 L), n is the number of moles, R is the ideal gas constant, and T is the temperature (which can be assumed to be room temperature), we can rearrange the equation to solve for n. Plugging in the values, we get n=0.1 moles. Since the gas is a product of the reaction between silver nitrate and magnesium nitrate, we know that the mole ratio between the two compounds is 1:1. Therefore, we can conclude that the initial mass of both silver nitrate and magnesium nitrate in the mixture is 0.1 moles each. Next, we need to determine the mass of the gas in the original mixture. Using the molar mass of the gas (which can be calculated from the given mass and volume), we can convert the moles to grams and get a mass of 46.4 g. Now, let us calculate the mass of water in the resulting solution. The volume of the resulting solution is given as 200 mL, and we know that the density of water is 1 g/mL. Therefore, the mass of water is 200 g. Since mass is always conserved in a chemical reaction, we can subtract the mass of water from the original mass of the gas to get the mass of the substances that dissolved in water. This mass is equal to the total mass of silver nitrate and magnesium nitrate in the original mixture, which is 46.4 g. Now, we can calculate the mass fractions of silver nitrate and magnesium nitrate in the original mixture by dividing their individual masses by the total mass and multiplying by 100%. The mass fraction of silver nitrate is 21.55% and the mass fraction of magnesium nitrate is also 21.55%. Finally, to calculate the mass fraction of the resulting solution, we divide the mass of the gas remaining in the solution (which is equal to the mass of the dissolved substances) by the total mass of the resulting solution, which is the mass of water (200 g) plus the mass of the dissolved substances. The resulting mass fraction is 2.24%.
