Fluids, Solutions and Their Behavior - Quiz 1 Flashcards Preview

Spring 2020 - Chemistry & Physics > Fluids, Solutions and Their Behavior - Quiz 1 > Flashcards

Flashcards in Fluids, Solutions and Their Behavior - Quiz 1 Deck (34)
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1

What are fluids?

  • Something that can flow
  • Can be liquid or gas
  • Basic forces cause fluids to flow
  • Assume shape of container

2

Hydrostatics

Study of fliuds that are NOT moving

Density and Pressure

3

Hydrodynamics

Study of fluids in motion

4

Pascal's Principle

The pressure applied to a confined fluid increases the pressure of the entire fluid by the same amount

5

Bouyancy

All fluids exert a bouyant force on immersed objects equally on all sides of the object

6

Archimedes Principle

An object immersed either totally or partially in fluid feels bouyant force equal to the weight of the fluid displaced

7

If an object sinks, the bouyant force is _____ than the true weight of the object.

If it floats, the bouyant force is ______ than the true weight of the object.

Less

Greater

8

Hydrometer

A weighted device that measures specific gravity of fluids

9

Flow Rate

Volume of fluid passing a point per unit time

Units of volume divided by time'

m3/s

10

Speed and Diameter

  • Narrowing of tube causes speed to increase tremendously
  • Flow rate remains the same.
  • Volumes remain the same, while shapes change
  • Fluid flows at greater speed through narrow part of tube

11

Bernoulli's Principle

As the speed of a fluid increases, the pressure exerted by the fluid decreases

Fluid pressure is inversely related to speed

 

EX: Lift of airplanes, show cutains sucked towards you whe you turn on shower

12

Venturi Tube Flowmeter

Device used to measure fluid speeds in pipes. 

Basis for neb treatment delivery.

13

Viscosity

Measure of a fluid's resistance to flow

High Viscosity = flow slower

Low Viscosity = flow faster

 

 

14

Poiseuille's Law

Describes resistance to flow through a tube

  • Pressure increases proportional to flow rate & gas viscocity
  • Small airway radius and longer distances increase flow resistance
  • R = (8 x L x n) / (π x r4)        *R: resistance, L: length, n: viscosity, r: radius
  • Reducing r by 16% will double R
  • Reducing r by 50% will increase R by 16x

***Only applies to laminar flow***

15

Reynold's Number

  • NR - dimensionless quantity used to characterize fluid flow
  • Measures tendency for turbulence to occur, (> 2000)

16

Relationship of Reynold's Number to viscosity

Inversely Proportional

17

Relationship of Reynold's Number to density, velocity, and tube diameter

Proportional

18

Solution

Homeogenous mixture that has one or more solutes uniformly dispersed

  • Solvent - the larger amount
  • Solute - the smaller amount

19

Molality (m)

m = moles solute / kg solvent

Never equal to Molarity

Useful for physical chemistry

20

Molarity (M)

M = moles solute / L solution

Never equal to molality

Useful for solution stoichiometry

21

Solubility

The amount of solute that will dissove in a given amount of solvent

  • Like Dissovles Like
  • Polar to Polar; Nonpolar to Nonpolar
  • EX:
    • Lidocaine Hydrochloride soluble in water/blood
    • Organic compounds, like most injectable meds, to be relatively insoluble in a water-based medium like blood. 

22

Saturated

Contains the max amount of solute

23

Supersaturated

Not a stable system

Contains more solute allowed by the solubility

EX: Solid out of solution
Bubbling out as gas

24

Miscible

When two liquids are soluble in eachother in all proportions

EX: Alcohol & Water

25

Solvation Process

Energy/Heat required to break/solvate chemical bonds

Energy to break bond > Energy released = Endothermic

Energy released > Energy to break bond = Exothermic

26

How does pressure effect solubility

Directly Proportional

  • For Gas: As pressure increases, solubility increases (w/ constant Temp)
    • Henry's Law

27

How does Temperature effect Solubility

  • Gas: As temperature increases, solubiilty decreases
  • Liquids and Solids: As temperature increases, solubility generally increase

28

Colligative Properties

  • Only depend on number of particles, not identity
  1. Vapor Pressure decrease w/ solute increase
  2. Boiling Point increase w/ solute increase
  3. Freezing Point decrease w/ solute increase
  4. Osmotic pressure increase w/ solute increase

29

Vapor Pressure

  • Results from most energetic molecules at surface escaping to gas phase
  • VPsolution solvent
  • Raoult's Law - VP of volatile component of a solution  = VP of pure substance x mole fraction of that substance

30

Boiling Point Elevation

  • Temperature at which VP of the material = ambient pressure
  • VP of a solution is decreased by adding nonvolative solutes, a higher temp needed to drive the VP up to where it equals ambient pressure
  • Boiling point increases as concentration of solutes increases. - directly proportion to molal concentration of solute. 
  • EX: Adding salt to water slightly increase BP