General Chemistry Answers

Using the Dalton’s Law of Partial Pressure, solve the problem below.

1. O2 is prepared by decomposing calcium chlorate (Ca(ClO3)2) and collecting 255 ml sample over water at 40℃ and a total pressure of 798 mmHg. What is the partial pressure of O2? What is the mass of the O2 collected?

Need a complete solution

In basic solution, Se2− and SO3

2− ions react spontaneously:

2Se2−(aq) + 2SO3

2−(aq) + 3H2O(l) ⟶

2Se(s) + 6OH−(aq) + S2O3

2−(aq) E°

cell = 0.35 V

(a) Write balanced half-reactions for the process.

(b) If E°sulfite is −0.57 V, calculate E°selenium.

A solution is prepared by dissolving 38.7g of nonelectrolyte into 218g of water.

The freezing point of the solution is measured to be -5.53°C. Calculate the

molar mass of the solute. kf of water = 1.86°C/m

The enthalpy and entropy change of a reaction are -3.9 kJ/mole and +56.6

J/mole K respectively at 25o C. What is the free energy change in kJ/mole?

Is this reaction always spontaneous, never spontaneous or does it depend on

the temperature?

N2(g)+3H2(g) --->2NH3(g)

If ΔH = -92.2kJ and ΔS= -0.1987kJ/K, what is ΔG for the reaction at 475°C

and at 5°C? Provide the answer in kJ. In each case, is the reaction

spontaneous?

Explain what is wrong with each of the following statements:

1. when n=4, l can be 1,2,3, or 4

2. when l=2, ml can be 2,3,4,5, or 6

3. orbitals where l=6 would be called m orbitals

4. the fifth energy level contains 4 sublevels

5. the quantum numbers n=3, l=2 describe one of the 3p orbitals

Tell how many electrons there can be, in a given atom, with the following sets of quantum numbers.

1. n=3

2. n=2, l=1

3. n=4, l=2, m_l =0

4. n=3, l=2, m_l =1, m_s =+1/2

5. n=7

A 3.215 kg unknown substance was transformed from solid to liquid by condensing 10.52 kg of steam under atmospheric condition

What is the initial temperature of steam in degF

What is the heat of fusion of the unknown substance in kj/g

A 458 mL of water at 21.5°C is in a calorimeter. If a gold at 99.7°C is in put into the calorimeter, the calorimeter becomes 25.3°C. Specific heat of gold= 0.129 J/g-K

How many grams of gold was put into the calorimeter?

How much heat was involved in the processes?

What is the wavelength of radui wave with a frequency of 1.5x10⁷Hz?