Posts by Jordin

Total # Posts: 14

Geography
What led to the end of Egypt's power in the Nile River valley

Math
2.4 meters

Geo 7th Grade
the answer is C.

Chemistry
Calculate the enthalpy change for the reaction: 2S(s) + 3O2(g) --> 2SO3(g) Use the following thermochemical equations: Reaction S(s) + O2(g) --> SO2(g) Delta H(in kJ) -296.8 2SO2(g) + O2(g) --> 2SO3(g) Delta H(in kJ) -197.0

Chemistry
Copper metal can be obtained by heating copper oxide in the presence of carbon monoxide, CO, according to the reaction: CuO(s) + CO(g) --> Cu(s) + CO2(g) Calculate Delta H° in kJ using the following thermochemical equations. Reactions 2CO(g) + O2(g) --> 2CO2(g) ...

Chemistry
The unbalanced equation for the combustion of ethanol is as follows: C2H5OH(l) + O2(g) ¨ CO2(g) + H2O(g) How much heat, in kJ, is liberated when 4.84 kg of C2H5OH(l) is burned? Species Delta H‹f (kJ/mol) H2O(g) -241.8 CO2(g) -393.5 C2H5OH(l) -277.7 Express...

Chemistry
A 2.25 g sample of hydrazine, N2H4, is burned in a bomb calorimeter that contains 6,402.45 g of H2O, and the temperature increases from 25.00° C to 26.17° C. The heat capacity of the calorimeter is 3.64 kJ/° C. Calculate Delta E for the combustion of N2H4 in kJ/g.

Chemistry
When 25.0 g of ethanol vapor condenses, 23.6 kJ of heat is released. How much heat is required in kJ to vaporize 254 g of ethanol?

chemistry
Oh ok, I see what I did now. Thank you for the help! : )

chemistry
Thank you! So, is this correct? moles HCl = M x L = .2409 X .01232 = .00297 moles Na2CO3 = 1/2 moles HCl (from the equation). = .00297 / 2 = .00148 g Na2CO3 = moles x molar mass .00148 X 106 = .157 %Na2CO3 = (mass Na2CO3/mass sample)*100 = ?? .157 / .2528 X 100 = 60.8%

chemistry
A 0.2528 g sample of a mixture containing sodium carbonate and sand requires 12.32 mL of 0.2409 M HCl(aq). Assuming that the sand does not react with the HCl(aq), what percentage of the mixture is sodium carbonate? Balanced equation: Na2CO3(s) + 2 HCl(aq) ¨ 2 NaCl(aq...

acrostic poem
ya Mum.

america government
what is an informal amendment

government
what is an informal amendment