# Joesph

Most popular questions and responses by Joesph-
## 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

*asked on March 9, 2016* -
## 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.

*asked on March 9, 2016* -
## 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

*asked on September 28, 2016* -
## 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?

*asked on September 28, 2016* -
## 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

*asked on September 29, 2016* -
## 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)

*asked on October 19, 2008* -
## 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

*asked on September 29, 2016* -
## 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

*asked on November 16, 2016* -
## 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)

*asked on November 16, 2016* -
## 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

*asked on October 27, 2016* -
## 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?

*asked on October 7, 2008* -
## 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

*asked on November 23, 2007* -
## 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

*asked on October 31, 2016* -
## Chemistry

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

*asked on April 30, 2016* -
## trig/precalculus

A crate weighing w pounds sits on a ramp positioned at an angle of x with the horizontal. The forces acting on this crate are modeled by the equation Mwcosx = wsinx, where M is the coefficient of friction. What is an expression for M in terms of x? A. M =

*asked on December 13, 2011* -
## Geography

How does Nike (TNC) create connections between different countries? And where does the TNC operate? How does Apple (TNC) create connections between different countries? And where does the TNC operate? Thank you. :)

*asked on August 31, 2017*