chemistry_notes_2024

Experimental Design Common Laboratory Apparatus Measuring Mass Name of Apparatus Accuracy of Apparatus All readings should be in Electronic mass balance 0.01 g 2 decimal places Digital stopwatch 0.01 s Nearest seconds Alcohol thermometer 0.5 degrees Celsius 1 decimal place (nearest .0 or .5) Measuring Volume Name of Apparatus Accuracy of Apparatus All readings should be in Measuring cylinder Half of the smallest division 1 or 2 decimal places (depending on the apparatus)

Burette 0.05 cm^3 2 decimal places Pipette 0.01 cm^3 1 decimal place Gas syringe 0.1 cm^3 1 decimal place Name of Apparatus Accuracy of Apparatus All readings should be in Collection of Gas The method used to collect a gas depends on the physical properties of the gas: Solubility in water Density: Less dense or denser than air? Take the molar mass of air to be approximately 30 g/mol Gas Collection Methods Water Displacement Suitable for gases that are insoluble in water

Downward Delivery Suitable for gases that are more dense than water Upward Delivery Methods for Drying Gases Using Concentrated Sulfuric Acid

Suitable for gases that are acidic/neutral in nature For Method 1 explain why the inlet tube is inserted into the concentrated sulfuric acid while the outlet tube needs to be above the concentrated sulfuric acid The inlet tube needs to be in the concentrated sulfuric acid so that gas needs to be bubbled into the acid to remove the water vapour. The outlet tube needs to be above the concentrated sulfuric acid so that the dry gas can escape. Using Calcium Oxide Suitable for gases that are basic/neutral in nature Using Fused Calcium Chloride

Suitable for gases that are acidic/alkaline/neutral (except for ammonia) For Method 3, explain what it meant by "fused" and why ammonia gas cannot be collected using this method. "Fused" means anhydrous (does not contain water) This method cannot be used to collect ammonia gas because ammonia would react with calcium chloride

Kinetic Particle Theory What is Kinetic Particle Theory? Matter is defined as any substance that has mass and volume. Kinetic Particle Theory The kinetic particle theory states that: All matter is composed of tiny particles that are in a constant state of motion (have kinetic energy.) Properties Properties Solid Liquid Gases Forces of Attraction between particles Strong attractive forces between particles Relatively strong attractive forces between particles BUT weaker than those in solid. Weak forces of attraction between particles

Arrangement of Particles Particles are orderly arranged in a fixed position. Hence, they have a fixed shape. It has a fixed volume as a solid cannot be compressed since its particles are already very close to one another with very little space between the particles. Particles are NOT held in fixed positions. They are arranged in a disorderly manner. Hence, they DO NOT have a fixed shape. Particles of a liquid are farther away from one another than a solid. However, they are still pack