KK

From data below, calculate the total heat (in J) associated with the conversion of 0.505 mol ethanol gas (C2H6O) at 101°C and 1 atm to liquid ethanol at 25.0°C and 1 atm. (Pay attention to the sign of the heat.)

Boiling point at 1 atm 78.5°C

cgas 1.43 J/g°C

cliquid 2.45 J/g°C

H°vap 40.5 kJ/mol

How fast must a 140. g baseball travel in order to have a de Broglie wavelength that is equal to that of an x-ray photon with = 100. pm?

Nitrogen oxides undergo many interesting reactions in the environment and in industry. Given the following information, calculate H for the overall equation:

2 NO2(g) + 1/2 O2(g) N2O5(s).

4 NO(g) + 3 O2(g) 2 N2O5(s), H = -447.4 kJ

2 NO(g) + O2(g) 2 NO2(g), H = -114.2 kJ

(a) H = ? kJ

A mercury mirror forms inside a test tube by the thermal decomposition of mercury(II) oxide.

2 HgO(s) 2 Hg(l) + O2(g) Hrxn = 181.6 kJ

(a) How much heat is needed to decompose 595 g of the oxide?

kJ

(b) If 288 kJ of heat is absorbed, how many grams of mercury form?

g

The density of a noble gas is 5.35 g/L at 3.00 atm and 0°C. Identify the gas.

When 36.3 L ammonia and 40.5 L oxygen gas at STP burn, nitrogen monoxide and water are produced. After the products return to STP, how many grams of nitrogen monoxide are present?

When 35.4 L ammonia and 42.0 L oxygen gas at STP burn, nitrogen monoxide and water are produced. After the products return to STP, how many grams of nitrogen monoxide are present?

(a) g

NH3(g) + O2(g) NO(g) + H2O(l) [unbalanced]

How many grams of phosphorus react with 34.5 L of O2 at STP to form tetraphosphorus decaoxide?

P4(s) + 5 O2(g) P4O10(s)

(a) g

To prevent the presence of air, noble gases are placed over highly reactive chemicals to act as inert "blanketing" gases. A chemical engineer places a mixture of noble gases consisting of 5.92 g of He, 15.6 g of Ne, and 36.6 g of Kr in a piston-cylinder assembly at STP. Calculate the partial pressure of each gas.

PHe = ? atm

PNe = ? atm

PKr = ? atm

any help would be mucho appreciated!

A sample of an unknown gas effuses in 10.2 min. An equal volume of H2 in the same apparatus at the same temperature and pressure effuses in 2.29 min. What is the molar mass of the unknown gas?

A sample of an unknown gas effuses in 11.1 min. An equal volume of H2 in the same apparatus at the same temperature and pressure effuses in 2.93 min. What is the molar mass of the unknown gas?

A 61 L sample of dry air is cooled from 143°C to -40.°C while the pressure is maintained at 2.85 atm. What is the final volume?

Calculate the volume of a sample of carbon monoxide at - 22°C and 320. torr if it occupies 3.65 L at 298 K and 761 torr

through what dates were the britsih in india?

Does everyone have atleast some form of ADD? So many people now days are being diagnosed with ADD or ADHD, why is this? Is this because maybe everyone does have ADD. Is it just that people can relate to the various symptoms and are being misdiagnosed? Are doctors more educated now and are able to spot it and label it more easily than before? Or coulld it be something in the training of children as they are brought up? What has caused this dramatic increase in the diagnosing of ADD?

NOT martin luther king.. martin luther

i need some ideas... who do you think are in the top five most important/influential people in the world over the past 1000yrs, and why?

i have a small red ear slider (about 2inches long) and i dont know what to fees him. he hasnt been eating the turtle food that i have been feeding him. the food came with the turtle too. personnally i think that maybe the food pellots are too big for him? what can i feed him? also... CAN i put him in aluminum?

i bought a red ear slider, but i want to put him in a big aluminum bowl/pan that i have. can i put it in aluminum? it is barely 2 inches long. so im concerned.