Results for "concentrations"

02 Solutions and Concentrations

Equilibrium Concentrations

Titration experiments: 4.3.4 Using concentrations of solutions in mol/dm3 (chemistry only) (HT only): AQA: GCSE (9:1)

SCIENCES : solutions et concentrations

**Properties of Matter** - **Physical vs Chemical Properties** - *Physical Properties:* Can be observed without changing the substance (e.g., color, density, melting point, boiling point) - *Chemical Properties:* Describe a substance’s ability to undergo chemical changes (e.g., flammability, reactivity with acid) - **Examples of Each** - Physical: Ice melting, water boiling, density, solubility - Chemical: Rusting iron, burning wood, tarnishing silver - **Intensive vs Extensive Properties** - *Intensive:* Do not depend on the amount of matter (e.g., density, boiling point, color) - *Extensive:* Depend on the amount of matter (e.g., mass, volume, length) --- **Density** - **Definition, Units, and Formula** - Density (ρ) = Mass (m) / Volume (V) - Units: g/cm³ (solids), g/mL (liquids), kg/m³ (gases) - **Comparison of Densities** - Solids: Generally highest density - Liquids: Lower density than solids but higher than gases - Gases: Lowest density - **Solid: Regular vs Irregular Shape** - *Regular Shape:* Use geometric formulas to find volume - *Irregular Shape:* Use water displacement method - **Factors Affecting Density** - Temperature (increase decreases density for most substances) - Pressure (affects gases significantly) - Composition (different materials have different densities) --- **Elements, Compounds, and Mixtures** - **Matter: Definition and Examples** - Anything that has mass and takes up space (e.g., air, water, rocks) - **Pure vs Impure Matter** - *Pure:* Elements and compounds (e.g., oxygen, water) - *Impure:* Mixtures (e.g., saltwater, air) - **Atom vs Element** - *Atom:* Smallest unit of an element - *Element:* Substance made of one type of atom - **Compounds vs Mixtures** - *Compounds:* Chemically bonded elements (e.g., H2O, CO2) - *Mixtures:* Physically combined substances (e.g., salad, air) - **Types of Mixtures** - Homogeneous (solutions, uniform throughout) - Heterogeneous (distinct parts, not uniform) - **Examples of Mixtures** - Homogeneous: Saltwater, air - Heterogeneous: Salad, granite --- **Solubility** - **Solutions** - *Parts:* Solute (dissolved substance) + Solvent (dissolving substance) - *Examples:* Saltwater (solute: salt, solvent: water) - **Effect of Temperature and Pressure** - Higher temperature increases solubility of solids in liquids - Higher pressure increases solubility of gases in liquids - **Gases vs Liquids** - Gases dissolve better in cold liquids under high pressure - Liquids dissolve better at higher temperatures - **Gaseous, Liquid, and Solid Solutions** - Gaseous: Air (oxygen in nitrogen) - Liquid: Saltwater (NaCl in H2O) - Solid: Alloys (brass, steel) - **Concentrations** - Unsaturated: Can dissolve more solute - Saturated: Maximum solute dissolved - Supersaturated: Holds more than normally possible - **Solubility Curve** - Shows solubility vs temperature - Higher points indicate higher solubility --- **The Mole** - **Avogadro’s Number** - 6.022 x 10^23 particles per mole - **Molar Mass** - Mass of one mole of a substance (g/mol) - **Particle, Mass, and Mole Calculations** - Particle calculations: Using Avogadro’s number - Mass calculations: Converting between grams and moles - Mole calculations: Determining amount of substance - **Moles at STP (Standard Temperature and Pressure)** - 1 mole of gas = 22.4 L at STP - **Atomic Mass Units (AMU)** - Unit for atomic/molecular mass --- **Labs** - **Density Lab** - Measure mass and volume, calculate density - Compare densities of different materials - **Elements, Compounds, and Mixtures Lab** - Classify substances based on their properties - **Mystery Powder Lab** - Identify unknown substances using solubility and reactions - **Cornstarch Lab** - Explore properties of non-Newtonian fluids This guide covers essential concepts in matter, density, solubility, and the mole, along with relevant lab activities

Applied Nutrition Lab 3: NSC Concentrations

The Skeletal System: Regulation of Blood Calcium Concentrations

1.5 b/ OZ 1- Gas Concentrations and Atmospheric Composition

1.5 b/ OZ 1- Gas Concentrations and Atmospheric Composition

Ion Concentrations to know

Chemistry - 4 Chemical Calculations - 4.6 Expressing Concentrations

Module-01-Thermodynamics-and-Concentrations-Review

ch 171 - chapter 7 (solubility, dissolution, solution concentrations)

Ch 4.1 : Solutions, Concentrations, Dilution

Concentrations and Dilutions

Key Concepts: Cell Theory, Cell Structure & Function, Prokaryotic vs. Eukaryotic, Cell Membrane, Microscopes, Passive vs. Active Transport, Diffusion, Osmosis, Energy (Potential vs. Kinetic), Photosynthesis & Cell Respiration (Aerobic vs. Anaerobic), Fermentation (Lactic Acid & Alcoholic) 1. Describe one similarity and one difference between the two terms in each of the following pairs: a. Eukaryote, prokaryote Eukaryote: Has a membrane-bound nucleus in the cell Prokaryote: No nucleus, DNA free-floating in the cell, can have flagellum Both: have cell membranes, have DNA, have ribosomes b. Cell wall, cell membrane Cell wall: rigid, not as flexible, more selective (harder for things to pass through) Cell membrane: fluid, flexible, selectively permeable Both: enclose cell, facilitate what goes in/out of cell c. Diffusion, facilitated diffusion Diffusion: movement of particles from high to low concentration Facilitated diffusion: movement of particles through channel proteins Both: are passive transport (no energy required), particles move from HIGH to LOW 2. Describe the structure of a phospholipid bilayer. There are 2 layers of phospholipids (consisting of hydrophilic heads and hydrophobic tails) 3. Explain the following diagram using the terms: diffusion, cell membrane, low concentration, energy, high concentration. The water molecules are moving across the cell membrane to reach a state of equilibrium. The molecules move from HIGH to LOW concentration, so they move downwards across the membrane. This is an example of diffusion, or passive transport - this does not require energy because it is fueled by the difference in concentrations. 4a. What is the microscope magnification of the eye piece? scanning? low power? high power? ● Eye piece = 10x ● Scanning = 4x ● Low power = 10x ● High power = 40x b. If you were looking at an onion cell using the high power lens, what is the TOTAL MAGNIFICATION at which you are looking at the cell? High power = 40x Eye piece = 10x 40 x 10 = 400x Your total magnification would be 400x using the higher power objective lens. 5. Identify the difference between hypertonic, isotonic, and hypotonic solutions: A = isotonic B = hypotonic C = hypertonic 6. How is active transport different from diffusion and facilitated diffusion? ● Active Transport = requires energy, molecules are forced AGAINST the gradient from LOW to HIGH concentration ● Diffusion = does not require energy, molecules move from HIGH to low concentration ● Facilitated diffusion = does not require energy, molecules move from HIGH to low concentration, but it requires the help of channel proteins (typically larger molecules) 7. Explain what is happening in the following picture. This is an example of ENDOCYTOSIS (Active Transport) - there is a chemical/nutrients being taken into the cell when it’s engulfed by the cell membrane (becomes a vesicle). 8. What is the difference between potential and kinetic energy? Give an example of each. a. Poyential energy - stored energy; e.g,glucose, a ball at the topof ahill b. Kinetic energy - energy of motion e.g., a car onthe freeway 9. Write out the full chemical reaction for PHOTOSYNTHESIS. What organelle is responsible for this? Chloroplast 10. Write out the full chemical reaction for CELL RESPIRATION. What organelle is responsible for this? Mitochondria 11. If we are at 400X magnification (field diameter is 450 micrometers), and there are 10 cells that fit across the diameter of what we’re seeing, what is the estimated size of ONE cell? 450 nanometers / 10 cells = 45 nanometers per cell 12. What is the role of the stomata? What is the role of the guard cells? Stomata role isgas exchange to let oxygen and carbondioxide pass through, as needed for key processes such as photosynthesis and cellular respiration. Guard cells arepairs of cells that surround the stomata and controlgas exchange by regulatingthe openingand closure of stomata. 13. What would cause guard cells to swell and open stomata? What would cause guard cells to shrink and close stomata? → Whentheplanthas anexcess of water, theguard cells swell and create anopeningfor the exchange ofgas → Whentheplanthas a lack of water, theguard cells shrink and close the openingfor the exchange ofgas 14. In fermentation, what relationship exists between the amount of available sugar and amount of carbon dioxide produced? → As more sugar is available, there will be more fermentationthathappens, and more carbondioxideproduced → There is a direct relationshipbetweenthose two factors 15. List the # of ATP produced by each of the following: Glycolysis = 2 ATP Krebs = 2 ATP ElectronTransport = 34 ATP 16. Explain one example of lactic acid fermentation. Explain one example of alcoholic fermentation. a. Lactic acid fermentation- heating milk and combiningit withtwo live bacteria cultures, resultinginthe bacteria breakingdownthe sugars in milk and releasinglactic acid (distinct tart/sour taste) b. Alcoholic fermentation- yeast and bacteria beingadded to tea and fruit (sugar), resultinginkombucha withethanol and carbondioxide bubbles

Lecture 3: Percentage Strength, Ratio Strength, Concentrations, and Other Methods of Potency (9.23.24)

Séance 7: Le contrôle de concentrations

Mixtures, Solution Concentrations, Osmosis and Dialysis

HOSA Medical Math Chapter 4 Dilutions, Solutions, and Concentrations