Question

Which is a characteristic of surface tension?

	a.	The molecules of a liquid form a porous network at the liquid’s surface.
	b.	The molecules of a liquid attract each other enough to prevent penetration by other molecules.
	c.	Surface tension is the same in various types of liquids.
	d.	Surface tension is greater in a nonpolar covalent liquid than a polar covalent liquid.

Between which species will ionic bonds be present?

	a.	two ethanol molecules
	b.	two chloride ions
	c.	two sodium ions
	d.	a sodium ion and a chloride ion

Which is true of the molecules described?

	a.	Sodium chloride is a polar covalent molecule.
	b.	Water is a nonpolar covalent molecule.
	c.	Ethane is a polar covalent molecule.
	d.	Ethanol is a polar covalent molecule.

Which best describes a hydrated sodium ion?

	a.	Each sodium ion is surrounded by many water molecules.
	b.	Each sodium ion is paired with a water molecule.
	c.	Each sodium ion is paired with a chloride ion.
	d.	Each sodium ion is paired with 2 water molecules.

How does an ionic solid dissolve in water?

	a.	Water molecules penetrate to the center of the ionic solid, causing the crystal to dissolve.
	b.	Each ion is paired with one water molecule as the ionic solid dissolves.
	c.	Each pair of ions is paired with two water molecules as dissolution occurs.
	d.	Water molecules are attracted to ions at the surface of the solid, surrounding each as they are displaced from the solid.

Answer 1

1) The surface tension results in the high force of attraction due to adhesion and cohesion. So option (b) is correct.

Surface tension is not equal in various types of liquids and the polar covalent liquids have high surface tension than non polar covalent liquids.

2)Ethanol is the polar covalent molecule and optuon (d) is correct.

Here water is polar, ethane is non polar and sodium chloride is polar but it is ionic molecule.

3) In hydration, each sodium ion is surrounded by many water molecules and option (A) is correct.

4)Water molecules firstly hydrate the ionic solid byatrracting to the surface of solid surrounding each other and therefore option (d) is correct.