The standard addition equation is as followsI_(S+X) (V/V_O )=I_X+I_X/[X]_i [S]_4 (V_S/V_0 ) Here, [X]_i is the initial concentration of analyte, [S]_i is the initial concentration of standard, I_X is signal for analyte, I_(S+X) is signal for standard and analyte, V_0 is the initial volume, V_S is the added standard volume, and V is the total volume.Added volume of standard V_S is-23.3 mL. Initial volume of the sample V_0 is 10.00 mL. Initial concentration of standard ([S]_i) is 0.156 ng/mL.[X]_i= -[S]_i (V_S/V_0 )〖[X]〗_(i )= -(0.156 ng/mL)((-23.3 mL)/(10.00 mL))=0.363 ng/mL
Concentration of U(III) in ground sample is 0.363 ng/mL
Hey there!
2.70 moles of Fe x (6.022 x 10^23) atoms of Fe = 1.63 x 10^24 atoms of Fe
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1 mole of Fe
Answer: 1.63 x 10^24 atoms of Fe
Hope this helps :)
If you double the concentration of A, the rate is doubled. If you doubled the concentration of B, since the rate law has B^2, the rate is multiplied by 4. If you double both A & B's concentrations, then the rate would be multiplied by 2*4 = 8, which is the last option.
