Heat of Reaction: How many grams of butane must be burned to release 6375kJ of heat?

The combustion of butane produces heat according to the equation 2C4H10(g) + 13O2(g) --> 8CO2(g) + 10H2O(l) deltaHrxn= -5314kJ How many grams of butane must be burned to release 6375kJ of heat?

At pH 6.00 and pE 2.60, what is the concentration of Fe2+ (mol/L) in equilibrium with Fe(OH)3?

At pH 6.00 and pE 2.60, what is the concentration of Fe2+ (mol/L) in equilibrium with Fe(OH)3? Hint: Use the Nernst equation and the Ksp for the solubility of solid iron (III) hydroxide. I would like to know how to set up the Nernst equation and where it is appropriate to plug in the valvue and how it correlates wo the co ...continues

chemical reactions

Why when heating and cooling three different separate substances in open containers does the mass change in two of them(one loss mass; the other gained mass) but stays the same in the third when it is known that mass is conserved in chemical reactions? Would it be because one gave off vapor, the second melted and the third was a ...continues

Single Replacement Reactions

Complete the balanced equation if a reaction will occur. State "does not occur" if the reaction will not take place. a. Na + H(NO3) ---> b. Ni(II) + Cu2O --> c. Zn + Mg(NO3)2 -->

center of mass

Hi-please explain steps taken to establish the center of mass with polar covalent bonds and dipole moments - why is this important?

KBr @ 60 Celsius - explain math

Attached is a graph-please explain how to find the solubility of KBr @ 60 Celsius.

highest vapor pressure at room temperature

Which would you expect to exhibit the highest vapor pressure at room temperature? Helium,(Delta H fusion 0.02, Delta H vap0.10) Benzene,( Delta H fusion 9.95, Hvap30.8) Water, (Hfusion6.01, Hvap40.67)or Mercury?(Hfusion 2.33, Hvap 56.9)

mole fraction

Hi-please explain math involved at an ELEMENTARY level(-: Thanks. At a given temperature the vapor pressures of benzene and toulene are 183 torr and 59.2 torr. Calculate the mole fraction of benzene in the vapor phase over a solution of benzene and toulene with X sub benzene = 0.600.

Vapor pressure

Hi-Please explain math as elementary as possible-thanks. The Vapor pressure of Ethanol is 115 torr at 34.9EC If H sub vap = 40.5 kJ/mol, calculate the temperature (in EC) at which the vapor pressure is 760 torr.

molarity of the sulfuric acid

Hi-Please explain math as ELEMENTARY as you can-thank you. A solution is prepared by dissolving 17.75 g Sulfuric acid (H2S04;MW = 98.0g/mol) in 93.2 g of water. If the density of the solution is 1.1094g/mL, what is the molarity of the sulfuric acid?