Non- Metal Chemistry The 6Non-metals you will be learning about are: oxygen, sulfur, nitrogen, carbon, chlorine and bromine.
Metals vs Non-metals • Metals and Non-metals • Metals are found on the left hand side of the periodic table and the non-metals are found on the right. Elements physical properties are used to characterise them as either a non-metal or metal. • The differences in the chemical properties of metals and non-metals are shown in the table below.
Makes up 78% of The atmosphere Used to create an Inert atmosphere & Used in refrigerant Found in amino Acids, proteins And nitrates Used to make Ammonia via the Haber process Gas at room temp Colourless, Tasteless and Odourless Nitrogen Commercial Production via Fractional Distillation. Has the same Density as air No lab test For nitrogen Has many Associated oxides Insoluble in water
The Nitrogen Cycle Nitrogen is essential for living things because it is used to make proteins. Proteins are the building blocks that make up all living things.
Uses of Nitrogen • Artificial fertilisers contain nitrogen compounds to help plants grow. • Liquid nitrogen. Nitrogen gas turns into a liquid at -195.8°C which makes it a good coolant. It is used to freeze warts and other biological material such as embryos for storage.
Several nitrogen compounds are highly explosive. E.g nitro-glycerine and TNT. • Nitrous oxide (N2O) is used as an anaesthetic.
Normally we do not absorb nitrogen from the atmosphere but when the air we breathe is pressurised, nitrogen gas can dissolve in your blood. N2 bubbles form in the blood. This is known as ‘the bends’.
Chemical Properties of Nitrogen Nitrogen gas comprises of two nitrogen atoms __________ bonded together, forming a triple bond. The bond is very _________ and requires a large amount of _________ to break. Only at very high ______________ or if an electrical spark is passed through nitrogen gas will it react with ____________. This does occur in the internal combustion engine.
Nitrogen Compounds Nitrogen dioxide NO2 Nitrogen monoxide NO Nitrates NO3- Nitrites NO2- Nitrogen reacts with Oxygen to produce Nitrogen cycle Dinitrogen Monoxide N2O Ammonia NH3 and Ammonium compounds NH4+ Nitric acid HNO3 Amino acids which are the Building blocks for all Proteins. NH2-CH2-COOH
Nitrogen Dioxide NO2 Nitrogen dioxide is a toxic gas with a choking smell. It has an irritating effect on humans, affecting the nose, throat and eyes. When it reacts with water it produces an acidic solution causing acid rain. It also is involved in the complex series of reaction, with other pollutants in the atmosphere producing photochemical smog.
Nitrous oxide N2OIt is also called dinitrogen oxide or laughing gas. It is a colourless slightly sweet smelling gas that is soluble in water producing a neutral solution. It has a slightly anaesthetic properties.This is a covalent compound that is produced when ammonium nitrate is heated.
Nitric oxide NOThis is also known as nitrogen monoxide or nitrogen oxide. It is a colourless gas that is soluble in water. It is a covalent compound made when copper reacts with 50% nitric acid. It then reacts with oxygen to form nitrogen dioxide.2NO + O2 → 2NO2Nitrogen compounds are formed when cars burn fuel. It is these compounds that are responsible for pollution in the air. To reduce the pollution that is caused by these nitrogen oxides, cars which run on unleaded petrol can be fitted with a catalytic converter. This uses a catalyst and high temperature in the exhaust pipe to remove oxides by reacting it with carbon monoxide.
Photochemical smog Photochemical smog is a form of local pollution caused by the internal combustion engine. Some of the chemicals produced and emitted by the engine (e.g unburnt fuel, oxides of nitrogen and sulfur dioxide) react in the presence of sunlight with other chemicals in the atmosphere. This results in a blue-brown haze which is photochemical smog.
Used in cleaning products Colourless gas Sharpe, pungent Smell. Properties Preparation: Calcium hydroxide + Ammonium chloride Made by the Haber process Very soluble in water Less dense than Air. Used to make fertiliser Reacts with Conc. HCl When it is in solution It has basic properties
Lab Preparation Mixture of calcium hydroxide and ammonium chloride. Mixture of calcium hydroxide + ammonium chloride
Fountain Experiment Concentrated ammonia solution Is heated to fill the flask with ammonia Gas. This also increase the pressure In the flask. The flask is removed from the Heat and the pressure decreases This causes the water to rush Into the flask dissolving the Ammonia gas in the process Decreasing the pressure more.
Haber Process This process produces ammonia gas that is required for the production of fertiliser. The process involves the reaction of nitrogen and hydrogen to produce ammonia. Nitrogen needed for the process is obtained from the atmosphere via fractional distillation.
Hydrogen is obtained from the reaction between methane (natural gas) and water. CH4 (g) + H2O(g) → 3 H2 (g) + CO(g) This is carried out at 750°C and 30 atmp with a nickel catalyst. The carbon monoxide is reduced with more unreacted steam to form even more hydrogen. CO(g) + H2O(g) → H2 (g) + CO2(g)
Nitrogen and hydrogen are then pressurised to approximately 200 atm and passed over a catalyst of iron at between 350°C and 500°C. The equation for the reaction is N2(g) + 3H2(g) → 2NH3(g) About 15% ammonia is produced it is collected and removed as a liquid.
Uses of Ammonia • Used to make pharmaceuticals • Commercial cleaning products • Fertiliser • Precursor to nitrogenous compounds • Refrigeration • As a fuel • Dye in woodworking • Antimicrobial agent in food • Stimulant • Prewash for wool.
Properties of Oxygen • Has the formula O2 • Colourless, odourless, tasteless, neutral gas • Slightly soluble in water. • mp -218°C and bp -183°C • Makes up 21% of the atmosphere and is removed via fractional distillation. • Very reactive and forms oxides with most other elements. • Consists as two allotropes O2 and O3 ozone. • Used by plants and animals for respiration.
Allotropes of Oxygen There are two allotropes of oxygen: O2 which is a molecule of oxygen and O3 which is ozone.
Ozone is found in the atmosphere. It is formed when solar radiation breaks the bonds in the oxygen molecules producing two oxygen atoms. These oxygen atoms react with another oxygen molecules to form ozone.
These ozone molecules absorb more radiation and break down into an oxygen molecule and an oxygen atom. Two oxygen atoms now join to form oxygen Ultraviolet radiation Oxygen atom Ozone Molecule Oxygen molecule Oxygen atom Oxygen molecule
The Ozone Hole Ozone is constantly being made and broken down but it is happening in balance.
Uses of Oxygen (O2) • Oxidation reactions- Burning, rusting and cell respiration. • In medicine, anaerobic bacteria that causes gangrene can be killed with oxygen. • Pure oxygen helps sick people who struggle to breathe. • Industrial furnaces and gas welding use oxygen to produce intense heat. • High altitude mountaineers, astronauts and pilots need to use oxygen.
Uses of Ozone (O3) • Ozone is known as natures most powerful disinfectant. It is used in air and water purification, deodorization and food sanitation. • Prevents electromagnetic radiation from reaching the earths surface.
Structure of Sulfur Sulfur is naturally found as a yellow solid. It is a molecular solid made up of ‘crown shaped molecule’ each containing 8 atoms. It is often called a pucked ring.
Facts • Sulfur is often found in volcanic regions. Such as Rotorua and White island in NZ. USA, Poland, Mexico, Sicily and Japan. • It is insoluble in water and does not conduct electricity. • It has a low melting point (119°C) and boiling point (444°C). • It is extracted by the Frasch process. • It burns in oxygen to produce sulfur dioxide. • It is used to make drugs, pesticides, matches and paper and is added to rubber to make it string. • Its also used to make sulfuric acid via the Contact process. • It can also be found in high amounts in crude oil and natural gas.