Hello! The mass percent composition of nitrogen in NH₄OH is 14/35×100. To find the percent composition by mass of an element within a chemical compound, divide the atomic mass of that element (AM), which is 14 for Nitrogen, by the entire compound's molar mass (MM) and multiply that by 100. The formula for determining percent composition is as follows: Have a nice day!
Hello, in this situation, the chemical reaction occurring is as follows: Next, we will ascertain the limiting reactant by calculating the moles of magnesium oxide produced from 3.86 g of magnesium and 155 mL of oxygen using the given mole ratios of 2:1:2 and applying the ideal gas equation, demonstrating that oxygen is the limiting reactant because it generates the least magnesium oxide. Subsequently, we determine the mass of magnesium consumed solely by the oxygen.
Based on the titration results, the adult would need to consume 85.7 mL to meet the recommended daily intake of 60 mg of Vitamin C. This is calculated from the average total volume of DCPIP used during trials.
The correct answer is Option A.
The calculation goes as follows:
Number of millimoles of Na3PO4 = 1 × 100 = 100
Number of millimoles of AgNO3 = 1 × 100 = 100
Dissociating 1 mole of Na3PO4 yields 3 moles of sodium ions and 1 mole of phosphate ions, whereas 1 mole of AgNO3 releases 1 mole of Ag+ and 1 mole of NO3-.
The Ag+ ion concentration becomes negligible since it forms a precipitate with the phosphate ion, indicating that the concentration of phosphate ions is also low.
With 100 millimoles of Na3PO4, we get 300 millimoles of Na+ and 100 millimoles of PO43-, and with 100 millimoles of AgNO3 we have 100 millimoles of Ag+ and 100 millimoles of NO3-.
Thus, the order of increasing concentration is: PO43- < NO3- < Na+.
