Chemistry

Which gas has a lower flammability limit of 2.5 and an upper flammability limit of 100 while in air at 25^circ C and 101 kPa? Ammonia Acetylene Ethanol Acetone

All combustion reactions are exothermic. When substances burn they usually give off energy as heat and light. True False

Using Delta G calculate the value of the thermodynamic equilibrium constant K for: H_(2)(g)+Br_(2)(l)- -gt 2HBr(g)

An aqueous solution is saturated in both oxygen gas and potassium iodide at 80^circ C Determine what happens when the solution is cooled to room temperature. Nothing happens. All of the oxygen gas and potassium iodide remain dissolved in solution. Potassium iodide precipitates out of the solution. Oxygen gas bubbles out of the solution and potassium iodide precipitates out of the solution. Oxygen gas bubbles out of the solution.

Lucy: What's up with the other elements that are in group 8, like Krypton. Do they have anything in common? a) They have the same number of electron shells b) They have the same number of protons c) They have the same atomic mass d) They have the same number of valence electrons

Multiple Choice Question Salt is __ chloride by weight. 40% 50% 60% 70%

Calculate the cell potential, E_(cell) for the reaction below when [Cr^3+]=0.25M and [Pb^2+]=0.15M 2Cr(s)+3Pb^2+(aq)leftharpoons 2Cr^3+(aq)+3Pb(s) E_(cell)^circ =+0.61V E_(cell)=0.597V E_(cell)=0.573V E_(cell)=1.09V E_(cell)=1.21V E_(cell)=0.871V

What term describes a solution where a solid dissolves in a liquid? soluble insoluble immiscible indissolvable

6) When 2,400 mg zinc is added to hydrochloric acid, 450 mL of hydrogen gas forms at a temperature of 30^circ C What is the pressure of the gas (in atm)? underline ( )Zn(s)+underline ( )HCl(aq)arrow underline ( )ZnCl_(2)(aq)+underline ( )H_(2)(g)

5) Determine the pressure (in mmHg) for the nitrogen gas sample that is collected when 53.0 g of NaN_(3) decomposes. The temperature of the gas is 25^circ C and the volume is 18.0 L. underline ( )NaN_(3)(s)arrow underline ( )Na(s)+underline ( )N_(2)(g)