Answer:
ΔH°rxn = -47 kJ
Explanation:
Using Hess´s law for the reaction:
3 Fe2O3(s) + CO(g) → 2 Fe3O4(s) + CO2(g) ,
the ΔH°rxn will be given by the expression:
ΔH°rxn kJ = 2ΔHºf(Fe3O4) + ΔHºf(CO2) - ( 3ΔHºf(Fe2O3) + ΔHºf(CO) )
= 2(-1118) + (-394) - ( 3( -824 ) + ( -111 ) )
= - 47 kJ
Nuclei may be unstable if they have
a too much energy.
b too many protons.
C an unstable ratio of protons to neutrons.
d any of the above.
The answer would be, D any of the above.
Hope this helps
Answer:
98.6 g/mol.
Explanation:
Equation of the reaction
HX + NaOH--> NaX + H2O
Number of moles = molar concentration × volume
= 0.095 × 0.03
= 0.00285 moles
By stoichiometry, 1 mole of HX reacted with 1 mole of NaOH. Therefore, number of moles of HX = 0.00285 moles.
Molar mass = mass ÷ number of moles
= 0.281 ÷ 0.00285
= 98.6 g/mol.
61.24 is the molar mass of a gas which has a density of 0.00249 g/mL at 20.0 degrees celcius and 744.0 mm Hg.
Explanation:
given that:
density = 0.00249 g/ml (
) or 2.49 grams/litre
P = 744 mm Hg OR 0.978 atm
T = 20 Degrees or 293.15 Kelvin
R = 0.08206 Litre atm/mole K
molar mass =?
Formula used/
PV = nRT equation 1
here n is number of moles:
n = 
putting the value of n and value of density in the equation 1:
PV =
x RT
molar mass =
x 
= density x 
= 
= 61.24 is the molar mass of the gas.
I'm pretty sure its metals that make good conductors.