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John Schreifels @GMU: What is the change in mass of 93Nb when it is formed from protons, electrons and neutrons if the atom has a mass of 92.9063772 amu? The masses of the proton, electron and neutron are 1.00728 amu, 0.000549 amu and 1.00867 amu, respectively.

@X@user.full_name@X@ @GMU: What is the activation energy (in kJ/mol) for the reaction below if the rate constants are 1.300 M-1s-1 at 427.00°C and 2.42 M-1s-1 at 446.39°C?NO2(g) + CO(g) → NO(g) + CO2(g)

@X@user.full_name@X@ @GMU: LiF has a face-centered cubic unit cell in which the F- anions occupy corners and face centers, while the cations fit into the hole between adjacent anions. What is the radius of Li+ if the ionic radius of F- is 136.0 pm and the density of LiF is 2.635 g/cm3?

@X@user.full_name@X@ @GMU: What is the standard free energy change for the following cell?3Cu2+(aq) + 2Cr(s) → 3Cu(s) + 2Cr3+(aq) Ecoell = 1.080V

@X@user.full_name@X@ @GMU: What is the concentration of OH- in 0.1796 M CH3COOH ? See reaction belowCH3COOH + H2O → CH3COO- + H3O+ Ka = 1.760×10-5

@X@user.full_name@X@ @GMU: What is the rate of consumption of A (M/s), if the rate of consumption of C is 0.261 M/s? Use the reaction below:2A + 3B + 4C → products

@X@user.full_name@X@ @GMU: By how much would the rate of reaction (see below) change if the concentration of Cl2 increased by a factor of 1.669. The rate law of this reaction is Rate = k[CHCl3][Cl2]1/2.CHCl3(g) + Cl2(g) → CCl4(g) + HCl(g)

@X@user.full_name@X@ @GMU: Which reactant in the reaction below is an acid (this one first in the answer) and which reactant is a base?F- + H2CO3 → HCO-3 + HF

@X@user.full_name@X@ @GMU: What is the activation energy (in kJ/mol) for the reaction below if the rate constants are 1.080e9 M-1s-1 at -78.00°C and 2.40e9 M-1s-1 at -54.17°C?NO(g) + O3(g) → NO2(g) + O2(g)

@X@user.full_name@X@ @GMU: What is the pOH of 3.49e-3 M H2SO4 ?