Question

can yall help worh these 3 questions please?

The strongest intermolecular forces between molecules of PH3 are dipole-dipole interactions. hydrogen bonds. ion-dipole attractions. London forces. QUESTION 10 Which of the following would be expected to have the lowest vapor pressure? H20 NH3 OPH₃ AsH3 QUESTION 11 Molarity and molality are different properties: The molarity of a solution is defined as the moles of solute per kilogram of solvent. moles of solute per liter of solution. moles of solute per liter of solvent. grams of solute per liter of solution.

Answer 1

Dear Student

HT H H London Dispersion forces - on polar molecules have symmetrical distribution of charge and have london forces between molecules. These are the weakest intermolecular forces of attraction. Hydrogen bonding . . Molecules having interaction between H & F or H&O or H&N due to high electronegativity of F, O N posses hydrogen bonding. Ion-dipole attractions - The intermolecular attraction between ionic compound and a polar covalent compound is called non-dipole attraction. Dipole-dipole attraction interactions - Polar molecules having / asymmetrical distribution of charge have dipule-dipole interactions. In a case of PH₂, it is a polar covalent molecule which don't have Hof, H-O or Hin bond (hydrogen bond). Hence PH₂ moleculas have de dipole-clipole interactions as strongest intermolecular forces (option first) I 10) Vapor pressure is the pressure exerted by the molecules that escape from the surface of liquid to a surrounding atmosphene. If the intermolecular forces of attraction of liquid is strong then less molecules and can escape to surrounding atmosphere from its surface, hence

lowering the vapod. pressure. Now, among NH₃, PH₂ and AsH₂, Nitrogen has more . extecto electronegativity as compared to P and As as we know that electronegativity decreases down a group and N, P, As belong to group no. 17. Since N is more electronegative it forms H-bond between moleculas and H bond is a strong intermolecular forces of attraction, Nom, between H₂O and NH3 OH bund is stronger than N-H bond as o is more electronegative them N. Hence H-bonding more strongen in H₂O than NH3 Since Ho has strongest intermolecular forces of attraction as compared to others it has the lowest rapors pressure. H₂O has lowest vapor pressure. (Option first) molality - It is the no. of moles of solute per kilogram of solvent. m= . no. of moles of solute mass of solvent (in kg) Mclarity. It is the no. of moles of solute per liter of solution ma no. of moles of solute - Volume of solution (in liter) 11) molarity is moles of solute per liter of solution. (Option and
Please give a positive rating to this answer. Thank you.