Exploring Properties of Matter

Properties of Matter

• Chemical properties include flammability, the ability to rust, and burning in air.
• Physical properties include state of matter, color, freezing point, boiling point, flexibility, volume, conductivity, density, texture, and size.
• The ability to burn is a chemical property because burning changes matter.
• Solubility is determined by dissolving the maximum amount of a substance in 1 L of water, and comparing the solubility of each solid with known values to identify them.
• Density is an intrinsic property that doesn't change with mass.
• To identify liquids, heat them until they boil, record their boiling points, and compare them with known values.
• Anything that has mass and takes up space.
• Physical properties do not depend on the amount of matter.
• Examples of physical properties include density, boiling point, freezing point and the index of refraction.
• Physical properties are observable without changing the material's identity, while chemical properties are observed when a material transforms into other substances.
• Iron is not used in utensils because it rusts easily.
• Matter consists of metals.

Measuring Matter

• Using standard units enables scientists to consistently understand and reproduce experimental procedures.
• Weight is measured using a spring balance.
• Mass is measured using a beam balance or electronic balance.
• An astronaut's weight changes in space since weight depends on gravity.
• To measure volume, immerse the solid in a known amount of water; the volume of water displaced equals the object's volume.
• Can calculate the amount of displaced water in this instance by finding the difference between volume readings before and after immersion.
• Density can be expressed as 4.5g/cm3

Volume and Density

• If one marble's volume is three times another's, its mass is also three times greater, but density remains the same.
• Density is an intrinsic property of matter.
• The order of liquid layers from top to bottom will be: oil, water then glycerin
• Mass measures the amount of matter in an object.
• Weight measures the pull of gravity on an object.
• Volume is the amount of space an object takes up.
• Density measures mass per unit volume.

Elements, Compounds, and Mixtures

• Different substances have different properties due to varying combinations of elements.
• A solution is a homogeneous mixture formed when substances dissolve in a solvent.
• An alloy is a solid solution with a metal solvent.
• A suspension is a heterogeneous mixture of stirred particles. If particles are small and don't settle, it forms a colloid.
• The smallest particle that retains an element's properties.
• An element cannot be broken down into simpler substances, while a compound consists of two or more elements in fixed ratios.
• A group of two or more atoms joined by chemical bonds is a molecule.
• Adding more solvent to the solution .
• Increasing the temperature of the solution.

Separation Techniques

• A separation technique recovers components from a mixture.
• Filtration separates mixtures with insoluble solids from liquids or gases, based on their states.
• Crystallization isolates a solid from a solution by reducing the solvent in a saturated solution.
• Paper chromatography separates mixture parts based on molecular structure differences.
• Filtration is suited to heterogeneous mixtures, separates the liquid while retaining the undissolved solid on the filter.
• Distillation involves boiling a solution then condensing the vapor.
• Fractional distillation is tailored for liquids with similar boiling points using a fractionating column.
• Add water to the mixture, recover the solid via filtration, separate paper clips from iron with a magnet, and recover sugar by crystallization.
• Fractional distillation is a form of distillation
• Distillation is a separation technique

Physical and Chemical Changes

• Cutting and folding aluminum foil illustrates physical changes.
• A physical change doesn't alter matter.
• The law of conservation of mass states that changes to matter don't create or destroy mass.
• A chemical change forms new substances.
• Chemical reactions rearrange atoms into new substances.
• Physical changes alter matter's properties without changing its chemical identity, while chemical changes produce new substances.
• Signs of chemical changes may include heat release, light production, or bubble formation.
• Oxygen is needed for combustion.
• Dissolving sugar in water and cutting hair are physical changes that don't form new substances.
• Mass is conserved during physical changes, so if the mass of water is 5g, it remains 5g.

Solids, Liquids, and Gases

• Solid particles are tightly bonded, maintaining a fixed shape and volume.
• Liquid particles are held together and can slide, allowing shape change but maintaining fixed volume.
• Gas particles are far apart, and changing the gas container will vary its shape and volume.
• Liquids and gases aren't rigidly bound as solids are.
• Pure substances comprise particles indivisible by physical changes.
• Increasing thermal energy will increases thermal energy,
• Decreasing the volume,
• The freezing point is defined as the temperature at which a substance freezes
• Cooling a substance slows its particles, leading to freezing as attractions hold them in place.
• Melting involves adding thermal energy, causing particles to overcome attractions and transition from solid to liquid.
• Evaporation occurs on a liquid's surface, while boiling involves a large-scale change from liquid to gas at a specific temperature.
• Sublimation is a physical change from solid to gas.
• Gas liquefaction reduces volume and eases handling.
• Condensation turns gas into liquid, while deposition turns gas directly into solid.
• A substance changes to a liquid when its temperature exceeds the melting point
• Snow's sublimation turns it directly into gas by gaining thermal energy.