Answer:
THE MOLAR MASS OF XCL2 IS 400 g/mol
THE MOLAR MASS OF YCL2 IS 250 g/mol.
Explanation:
We derive the molar mass of XCl2 and YCl2 by recalling the molar mass formula when both mass and the number of moles are known.
Number of moles = mass / molar mass
Molar mass = mass / number of moles.
For XCl2,
mass = 100 g
number of moles = 0.25 mol
Thus, molar mass = mass / number of moles
Molar mass = 100 g / 0.25 mol
Molar mass = 400 g/mol.
For YCl2,
mass = 125 g
number of moles = 0.50 mol
Molar mass = 125 g / 0.50 mol
Molar mass = 250 g/mol.
Accordingly, the molar masses for XCl2 and YCl2 are 400 g/mol and 250 g/mol, respectively.
Answer: The mole fraction of hydrogen gas at 20°C is 0.975
Explanation:
The information provided includes:
Water vapor pressure at 20°C is 17.5 torr
Total pressure at 20°C = 700.0 torr
Hydrogen gas vapor pressure at 20°C = (700.0 - 17.5) torr = 682.5 torr
To find hydrogen gas's mole fraction at 20°C, we utilize Raoult's law, represented by:

where,
= pressure of hydrogen gas = 682.5 torr
= total pressure = 700.0 torr
= mole fraction of hydrogen gas =?
Substituting the values into the equation yields:

Thus, the mole fraction of hydrogen gas at 20°C equals 0.975
The correct equation is (C) H3O+(aq) + C2H3O2−(aq) -> HC2H3O2(aq) + H2O(l). A buffer system is composed of a weak acid and its corresponding salt, effectively stabilizing the pH levels within a solution. The buffer works by adjusting the concentrations of the conjugate acid and base, maintaining the pH constant.
Answer:
- A. Which element, X or Z, has a higher molar mass?
Explanation:
Heating the original compounds intensely to remove all oxygen causes chemical decomposition reactions:
- 2XClO₃ (solid) → 2XCl + 3O₂ (gas)
- 2ZClO₃ (solid) → 2ZCl + 3O₂ (gas)
By measuring the initial mass of each sample and the mass remaining after heating, the student can compute the oxygen gas mass released:
- Mass of oxygen released = initial sample mass minus residue mass
Using this oxygen mass, she can calculate how many moles of oxygen were present in each sample:
- Moles of oxygen = oxygen mass (g) divided by molar mass of oxygen
Next, the moles of the original sample are determined:
- Each mole of XClO₃ or ZClO₃ has 3 moles of oxygen atoms.
So, dividing the moles of oxygen released by 3 gives the moles of the sample.
Applying the formula molar mass = mass / moles, the student finds the molar masses of XClO₃ and ZClO₃.
Thus, this data allows answering question A: Which of X or Z has the higher molar mass?
A secondary alkyl halide would be characterized by having a carbon atom connected to two other carbon atoms, with bromine attached to that carbon.
Therefore, bromo-hexane qualifies as a 2-degree or secondary alkyl halide