To solve this problem, we need to go step by step and analyze the provided information. Let's break it down:
(1.)
a) From the given information, element M reacts with an aqueous solution of compound B (HX) to form compound C, which contains elements M and X, and a gas composed of element D.
b) The student dissolves 1.000g of HX in enough water to make a 50.00ml solution and titrates it with 0.5000 M KOH. This requires 54.79ml (of 0.5000 M KOH) to reach the end point.
c) Compound MO is formed when 1.658g of M reacts with excess oxygen.
From this information, we can deduce the following:
- Element M reacts with HX, which is a hydrogen halide. To form 1 mole of compound MO, 1 mole of M reacts with 1 mole of HX.
- According to the titration, 1 mole of HX requires 1 mole of KOH for neutralization. Therefore, the molar ratio between HX and KOH is 1:1.
Based on these deductions, we can write the balanced equation for the reaction between M and HX:
M + HX -> MO + D
(2.)
To determine the mass of compound C formed, we need to calculate the moles of M and HX involved in the reaction and then consider the stoichiometry of the reaction.
- Moles of M = mass of M / molar mass of M
- Moles of HX = molarity of HX * volume of HX solution (converted to liters)
Using the balanced equation, we can determine the stoichiometry:
1 mole of M reacts with 1 mole of HX to form 1 mole of MO and 1 mole of D.
Since the molar ratio between M and MO is 1:1, the moles of M and MO formed will be equal.
To calculate the mass of compound C, we need to determine its molar mass and multiply it by the moles of MO formed.
(3.)
To calculate the volume of gas D (element D) collected, we need to use the ideal gas law:
PV = nRT
Assuming STP conditions (T = 273 K, P = 1 atm), we can convert the given pressure to atm and use the equation to calculate the moles of gas D. Then, we can convert the moles to volume using the ideal gas law equation, rearranged to solve for volume (V):
V = nRT / P
(4.)
To determine the moles of any reactant left over after the completion of the reaction, we need to calculate the initial moles of each reactant and then compare them with the moles used in the reaction.
- Moles of M initially = mass of M / molar mass of M
- Moles of HX initially = molarity of HX * volume of HX solution (converted to liters)
From the balanced equation, we know that 1 mole of M reacts with 1 mole of HX. By comparing the initial moles with the moles used in the reaction, we can determine which reactant is in excess and therefore, how many moles are left over.