1. In base alle tue conoscenze sui legami chimici, prevedi il legame che caratterizza la formazione della fosfina \( \mathrm{PH}_{3} \) \( \begin{array}{lllll}\text { A. Metallico } & \text { B. lonico } & \text { C. Covalente omopolare } & \text { D. Covalente eteropolare } & \text { E. Covalente dativo }\end{array} \)

Which of the following represent a buffer system? Check all that apply. \( \square \mathrm{NaOH} \) and NaCl \( \square \mathrm{H}_{2} \mathrm{CO}_{3} \) and \( \mathrm{NaHCO}_{3} \) HF and KF KCl and NaCl

Please select polar molecule(s) from the following. \( \square \mathrm{CCl} 4 \) \( \square \mathrm{CHCl} 3 \) \( \square \mathrm{CO} 3 \) CO 2

The pH scale for acidity is defined by \[ \mathrm{pH}=-\log \left[\mathrm{H}^{+}\right] \] where \( \left[\mathrm{H}^{+}\right] \)is the concentration of hydrogen ions measured in moles per liter (M). a) A sample of rhubarb is found to have a hydrogen concentration of 0.000501 M . What is the pH? Round your answer to 2 decimal places. \( \mathrm{pH}=\square \) b) The pH of a sample of red onion is 5.40 . What is the hydrogen concentration? Keep at leost 2 non-zero decimal ploces. \( \left[\mathrm{H}^{*}\right]=\square \)

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

Based on your worksheet results, please match the following: The electron group geometry of CCl 4 is The electron group geometry of CHCl 3 is [Choose ] [Choose ] The electron group geometry of \( \mathrm{SO}_{3} \) is [Choose ] [Choose ] electron group geometry of H 2 O is [Choose ]