Liquids boil at the temperature at which the vapor pressure is equal to the pressure on the liquid from its surroundings. Raising the pressure on a gas therefore effectively increases the boiling point of the liquid. Suppose that we have water vapor (or steam) in a closed container at 120oC and 1 atm.
http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch14/property.php
1 Viscosity is a measure of the ease with which molecules move past one another. 2  It depends on the attractive force between the moleculees.  It depends on whether there are structural features which may cause neighboring molecules to become entangled.
http://www.mikeblaber.org/oldwine/chm1045/notes/Forces/Liquids/Forces03.htm
Surface tension and viscosity are two interesting properties of fluids which are related to the cohesion of the molecules in the fluid. Viscosity is the resistance of a substance to flow (1) and surface tension is a property of liquids such that their surfaces behave like a thin, elastic film (1). Surface tension is created by the inward pulling force exerted on the surface of a fluid (2).
http://www.emerginginvestigators.org/2014/09/on-the-relationship-between-viscosity-and-surface-tension/
The viscosity test was designed based on the fact that viscosity is the resistance of a substance to flow. When a fluid’s time to flow through a tube is measured, it can be converted into flow rate (the higher the flow rate, the lower the resistance). A fluid with a higher viscosity would have lower flow rate. Viscosity tests were conducted to show the difference in viscosity between solutions.
http://www.emerginginvestigators.org/2014/09/on-the-relationship-between-viscosity-and-surface-tension/
Making the world better, one answer at a time. Attractions between molecules may affect the viscosity of a liquid because if the molecules aren't attracted close enough together, the viscosity will be much lower (the liquid will have a watery appearance). If the molecules are closer together, the liquid will have a higher viscosity. 
http://www.answers.com/Q/How_does_the_attraction_between_molecules_affect_the_ability_of_a_liquid_to_flow
Gases can't be liquified at temperatures above the critical temperature because at this point the properties of gases and liquids become the same, and there is no basis on which to distinguish between gases and liquids. The vapor pressure of a liquid at the critical temperature is called the critical pressure (Pc).
http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch14/property.php
In other words, the friction between neighboring particles in a fluid causes the viscosity. Viscosity results from the strength of the attraction between the particles of the liquid (5). Surface tension can be understood as a downward net attraction exerted on the surface of a fluid (1).
http://www.emerginginvestigators.org/2014/09/on-the-relationship-between-viscosity-and-surface-tension/
There is a force of attraction between molecules in liquids, and liquids can flow until they take on the shape that maximizes this force of attraction. Below the surface of the liquid, the force of cohesion (literally, sticking together) between molecules is the same in all directions, as shown in the figure below.
http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch14/property.php
The inward molecular attraction forces, which must be overcome to increase the surface area, are termed the surface tension. Surface tension is the energy required to increase the surface area of a liquid by a unit amount.
http://www.mikeblaber.org/oldwine/chm1045/notes/Forces/Liquids/Forces03.htm
Attractions between molecules may affect the viscosity of a liquid because if the molecules aren't attracted close enough together, the viscosity will be much lower (the liquid will have a watery appearance). Minor edit?
http://www.answers.com/Q/How_does_the_attraction_between_molecules_affect_the_ability_of_a_liquid_to_flow
explain how viscosity is related to the flow of attraction
Viscosity is related to the flow of attraction in a way that if the molecules aren't attracted close enough together, the viscosity will be much lower and if the molecules are closer together, the liquid will have a higher viscosity. Attractions between molecules may affect the viscosity of a liquid because if the molecules aren't attracted close enough together, the viscosity will be much lower or the liquid will have a watery appearance. If the molecules are closer together, the liquid will have a higher viscosity.