In Exercises \( 13-16 \), use the following information. Negative ions, designated by the notation \( \left[\mathrm{OH}^{-}\right] \), are always present in any acid or base. The concentration, \( \left[\mathrm{OH}^{-}\right] \), of these ions is related to \( \left[\mathrm{H}^{+}\right] \)by the equation \( \left[\mathrm{OH}^{-}\right] \cdot\left[\mathrm{H}^{+}\right]=10^{-14} \) moles per liter. Find the concentrations of \( \left[\mathrm{OH}^{-}\right] \)and \( \left[\mathrm{H}^{+}\right] \)in moles per liter for the substances with the following pH values. 13. \( \mathrm{pH}=6 \) 14. \( \mathrm{pH}=8 \) 15. \( \mathrm{pH}=9.5 \)

Please select the molecule(s) with double bond(s) from the following. \( \mathrm{CCl}^{2} \) CHCl 3 CO 3 H 2 O None

Please select the molecule(s) that 1) its molecular shape is different from its electron group shape, and/or 2) the central bonds are not identical. NH3 BF3 PFF PF3

L'uraninite, ou pechblende, est un minéral de formule chimique \( \mathrm{UO}_{2} \). Les gisements d'uraninite sont datés uniquement entre 3,5 et 2,2 milliards d'années. Its sont utilisés notamment pour extraire l'uranium uti- lisé dans l'industrie nucléaire civile et militaire. Ces gisements se forment dans des milieux réducteurs, c'est-à-dire en absence de dioxygène. Question Expliquer en quoi l'uraninite est un indice de l'évolution de la teneur en dioxygène terrestre.

Based on your worksheet results, please match the following: [he molecular shape of NH 3 is [Choose ] [Choose ] [Choose ] [Che molecular shape of BF3 is [Choose] The molecular shape of PF3 is

Please select the molecule(s) with resonance structures from the following. CCl 4 CHCl 3 SO 3 H 2 O None