# Joesph

Most popular questions and responses by Joesph
1. ## Chemistry

The Li2+ ion is hydrogenic and has a Lyman series at 740747 cm-1, 877924 cm-1, 925933 cm-1,and beyond. Show that the energy levels are of the form –hcR/n^2 and find the value of R for this ion. Go on and predict the wavenumbers of the two longest

2. ## Chemistry

Calculate the mass of the deuteron given that the first line in the Lyman series of H lies at 82259.08 cm-1 whereas that of D lies at 82281.476 cm-1. Calculate the ratio of ionization energies of H and D.

3. ## Chemistry

The standard change in internal energy for the combustion of buckyball is -25,968 kJ/mol. What is the enthalpy of combustion? What is the enthalpy of formation of buckyball? What is the molar enthalpy associated with converting buckyball to graphite? How

4. ## Chemistry

How high can a person (assume a weight of 70 kg) climb on one ounce of chocolate if the heat of combustion (628 kJ) can be converted completely into work associated with vertical displacement?

5. ## Chemistry

You want to heat 1 kg of water 10 degrees celsius and you have the following methods under consideration. The heat capacity of water is 4.184 J/K g. (a) You can heat it with a mechanical eggbeater that is powered by a 1-kg mass on a rope over a pulley. How

6. ## Calculus

Could someone please check my work on the following problems? I want to be sure that I'm doing them correctly; i'm just required to find the derivatives and then simplify. g(t)= t/sint g'(t)=1*sint-cost*t/(sint)^2 g'(t)=sint-cost*t/(sint)^2 y=ln(e^ax)

7. ## Chemistry

You want to heat 1 kg of water 10 celsius and you have the following methods under consideration. The heat capacity of water is 4.184 J/K g. (a)You can send the water through a solar collector that has an area of 1 m^2. How long will it take if the sun's

8. ## Chemistry Heat Capacity

Is ΔCP for the reaction > 0 or < 0? Would an atmosphere of 20% carbon dioxide, 5% carbon monoxide, and 75% nitrogen oxidize nickel at 1000K? It is given that ΔG° = -66.62 KJ/mol, ΔH° = -48.93 kJ/mol, and ΔS = 17.69 J/ mol K

9. ## Chemistry

For gaseous n-pentane and isopentane, both at 298K, ΔGf°=−194.4kJ/mol and−200.8kJ/mol, respectively. The vapor pressures of the liquids are given by: n-pentane:log10P(atm)=3.9714−1065/T−41 isopentane:log10P(atm)=3.9089−1020/T−40 Calculate (a)

10. ## Chemistry

Consider a mole of gas obeying the equation of state P⋅V = n⋅R⋅T + n⋅B(T)⋅P. Find w, q, ΔU, ΔS, ΔH, ΔA, and ΔG for a reversible isothermal expansion of this gas. Express your answers in terms of initial and final pressures, T, B, and

11. ## CALC I

z=cos(4 theta) what is the derivative. I know that the derivative of cos is -sin, but what do i do with the 4 theta. does that just become 4?

12. ## diversity?

I have to write an autobiographical research paper on race in my community. 1. The paper must have an introduction & thesis statement. 2. Body supporting evidence and in text citations. 3. conclusion. 4. three references. I am totally lost and don't know

13. ## physical chemistry

Calculate the freezing point of water at a depth of 10.0 cm below the surface of the water. The density of the water is 0.9998 g/cm3

14. ## Chemistry

Classify the following as pi-donating, pi-accepting, or pi-non-bonding. NH3,H2O,H2S