# Posts by Bru

Total # Posts: 12

math
10/11, 9/10, 8/9, 7/8

Physics
8.5

chemistry
calculate the standard molar entropy change for the combustion of methane gas using S naught values from standard thermodynamic tables. Assume that liquid water is one of the products.

chemistry
nevermind, I got it. Is the answer 160 g/mol?

chemistry
What do you mean solve for molar mass? I think that is the problem that I am having.

chemistry
A 250.0 mL sample of an aqueous solution at 25 degrees Celsius contains 35.8 mg of an unknown nonelectrolyte compound. If the solution has an osmotic pressure of 11.25 mmHg, what is the molar mass of the unknown compound? a.) 237 g/mol b.) 484 g/mol c.) 351 g/mol d.) 699 g/mol...

chemistry-lattice energy
Determine the lattice energy for CaBr2 if the enthalpy of solution for CaBr2 is -145 kJ/mol, and the heats of hydration for Ca2+ and Br- are -1650 kJ/mol and -292 kJ/mol respectively.

chemistry
So you invert the equation to M=pi/RTi to solve for Molarity. I plug in the numbers ((0.1480 atm)/(0.08206 L atm/K mol)(298K) (1)) That equals 6.1554*10^-4 mols. Dont you divide 0.358g/6.1554*10^-4??

chemistry
a substance has a vapor pressure of 35.0 mmHg at 52.0 degrees Celsius and 70.0 mm Hg at 77.0 degrees Celsius. What is the heat of vaporization for this substance?

physics
Resultant force= 4N Acceleration= 2ms-2

social studies
Are you really that lazy