Physical Chemistry Answers

List three trace elements that are concentrated in the Earth's crust relative to the mantle, and explain why.      

An experimenter places 15.0 mmol of A and 18.0 mmol of B in a container. The container is heated to

600 K, and the gas-phase equilibrium A + B ↔ 2C + 3D is established. The equilibrium mixture is found to

have pressure 1085 torr and to contain 10.0 mmol of C. Calculate Kp

θ

and ∆G

θ

at 600 K, assuming ideal

gas.

How long would it take (in seconds) to replace all of the hydrogen gas in a fuel cell that can accommodate 4.8 kg of hydrogen (H₂). If the current supplied to the cell is 10,000 A? 

½ O₂ + 2H⁺ + 2e- → H₂O         E⁰ = +1.23 V

2 H⁺ + 2 e- → H₂                               E⁰ = 0.00 V

F = 96,500 C/mol

. If the standard voltage of the reaction of Cu(s) with Ag⁺(aq) in the question above is +0.46V, what is the standard free energy change, DG^o, for the reaction?

Determine whether the statement is true or false, and why. “If a theory becomes supported by evidence, it can become a law.”

 Two excited states of the C2 molecule have the valence electron configurations below.

Assign to each all the possible term symbols: [8]

i) 1𝜎21𝜎21𝜋31𝜋1 and 𝑔𝑢𝑢𝑔

ii) 1𝜎21𝜎21𝜋21𝜋2 𝑔𝑢𝑢𝑔

What volume of 1.5N NaOH is needed to react with 25ml 4.0N HCl?