Answer:
True => ΔH°f for C₆H₆ = 49 Kj/mole
Explanation:
See Thermodynamic Properties Table in appendix of most college level general chemistry texts. The values shown are for the standard heat of formation of substances at 25°C. The Standard Heat of Formation of a substance - by definition - is the amount of heat energy gained or lost on formation of the substance from its basic elements in their standard state. C₆H₆(l) is formed from Carbon and Hydrogen in their basic standard states. All elements in their basic standard states have ΔH°f values equal to zero Kj/mole.
Answer:
For part (a): pHsol=2.22
Explanation:
I will show you how to solve part (a), so that you can use this example to solve part (b) on your own.
So, you're dealing with formic acid, HCOOH, a weak acid that does not dissociate completely in aqueous solution. This means that an equilibrium will be established between the unionized and ionized forms of the acid.
You can use an ICE table and the initial concentration ofthe acid to determine the concentrations of the conjugate base and of the hydronium ions tha are produced when the acid ionizes
HCOOH(aq]+H2O(l]⇌ HCOO−(aq] + H3O+(aq]
I 0.20 0 0
C (−x) (+x) (+x)
E (0.20−x) x x
You need to use the acid's pKa to determine its acid dissociation constant, Ka, which is equal to
Thermal energy is defined as the total kinetic energy of all particles in an object. Even though the cup of water has a higher temperature, the bathtub has more thermal energy because it contains much more mass of water compared to the cup.
Answer:
Explanation:
The water table or phreatic surface
Answer:
Mole fraction H₂ = 0.29
Partial pressure of H₂ → 88.5 kPa
Explanation:
You need to know this relation to solve this:
Moles of a gas / Total moles = Partial pressure of the gas / Total pressure
Total moles = 3 mol + 7.3 mol → 10.3 moles
Mole fraction H₂ → 3 moles / 10.3 moles = 0.29
Mole fraction = Partial pressure of the gas / Total pressure
0.29 . 304 kPa = Partial pressure of H₂ → 88.5 kPa
