Hydrogen–deuterium exchange of the carbon-bound C(8)-H protons of the inosine residues in tetrakis(inosine)platinum(II) chloride, S, with Pt binding at N(7), was studied in aqueous buffer solutions at 60 °C by ¹H NMR spectroscopy. The kinetics at all four C(8) sites as a function of pD of the D₂O/OD⁻ medium was measured through the disappearance of the C(8)-H signal, which yielded the pseudo first-order rate constant for exchange, k_obs. Plots of k_obsversus [OD⁻] showed curvature reminiscent of saturation type kinetics and indicative of competitive deprotonation of N(1)-H sites. In contrast, the analogous N(1)-methylated cis-bis(1-methylinosine)diammineplatinum(II) chloride leads to a linear k_obsversus [OD⁻] plot. The potentiometrically determined macroscopic composite N(1)-H ionization constant was further dissected into the successive microscopic N(1)-H acidity constants of the four inosine residues of the complex S. The k_obs values were also deconvoluted into individual rate constants k_ex (i.e.k₀, k₁, k₂, k₃ for exchange of the successively deprotonated inosine moieties, S, S₁, S₂, S₃, it being assumed that S₄ where all four inosine ligands are deprotonated at N(1) is unreactive (“immunized”) to exchange. The k_ex values show a progressive attenuation in Pt activation of H–D exchange along the series, k₀, k₁, k₂, k₃. The k_ex data thus generated, together with the deconvoluted individual pK_a values allow the construction of the plot, log k_ex [C(8)-H] vs. pK_a [N(H)-1]. Remarkably, this plot exhibits good linearity (R² = 0.99), which accords this as a linear free energy relationship (LFER). The large negative slope value (−2.3) of this LFER reflects the high sensitivity of transmission of electron density from the ionized N(1)viaPt and/or through space to the remaining C(8)-H sites. This is to our knowledge the first instance in which a LFER is generated through modulation of a structure in a single molecule. One can anticipate that this approach may lead to: (1) predicting N-H acidity; (2) C-H H–D exchange susceptibility in a range of metal–biomolecule complexes; (3) their carbon acidity.