4. A
because PbCl2 is an ionic compound and it's solid, so it's a substance.
It cannot be mixture, because it's a pure molecule.
5. D
despite that both substances are gases, colorless they are different molecules, so they should have different either chemical and physical properties
6. C
this substance made from W atoms and others are made from molecules
Answer:
A . 6.3 In a healthy pond, the temperature is 16°C (61°F). What is the most likely pH of this pond
Answer:
(A) The intermolecular attraction between HF molecules are stronger than between HCl molecules mainly to due hydrogen bonding.
Explanation:
Since Flourine is highly electronegative and as such, when it bonds with Hydrogen it forms a hydrogen bond. Whereas the HCL molecule is a polar molecule whose inter-molecular forces are dipole dipole interactions. Although a Hydrogen bond is a type of dipole dipole interaction it is stronger than the traditional dipole dipole forces and London dispersion forces. HF also has a shorter bond length which makes the bond and inter-molecular forces stronger as compared to HCL.
Neutral ion because f das fds f d fd f d f f sdf f sd fds
