Flashcards
chemistry 1
Cards in this deck (96)
- 1C1fundamental ideas
rocks and building materials
metals and their uses
crude oil and fuels
products from oil
plant oils
our changing planet - 2What substances are shown in the periodic table?Elements
- 3What is in an atom?An atom is made up of a tiny nucleus surrounded by electrons
- 4why are atoms neutral?the nucleus of an atom contains protons with a +1 charge, it also contains electron with a -1 charge. The number of electrons is the same as the number of protons therefore there is no overall charge
- 5What is the atomic number?this is the number of protons in an element
- 6what is the mass number?this is the amount of protons and neutrons in the element
- 7why are the noble gases stable?they have a full outer shell
- 8what is formed when a metal reacts with a non-metal?an ion
- 9how is an ionic bond formed?metals lose electrons to form positively charged ions, non-metal atoms gain electrons to for negatively charged ions. The oppositely charged ions attract each other strongly and the compound has a ionic bond
- 10how is a covalent bond formed?when non-metals combine, their atoms share electrons to form covalent
- 11what is limestone used to make?cement
concrete - 12what do metal carbonates produce when heated strongly?they produce metal oxide and carbon dioxide
- 13why is limestone damaged by acid rain?the calcium carbonate in the limestone reacts with the acid in the rain
- 14what is calcium hydroxide solution called?limewater
- 15what is the test for carbon dioxide?the limewater turns cloudy when carbon dioxide is present
- 16when limestone is decomposed what is produced?carbon dioxide
calcium oxide - 17what is produced when calcium oxide is mixed with water?calcium hydroxide
- 18what is produced when adding more water to calcium hydroxide?calcium hydroxide solution (limewater)
- 19what is produced when adding carbon dioxide to calcium hydroxide solution?calcium carbonate (limestone)
- 20how do you make cement?limestone is mixed with clay and heated strongly in a kiln
- 21how do you make mortar?add sand and water to the cement
- 22what is mortar used for?to hold bricks and blocks together
- 23how is concrete made?add aggregate to cement, then sand and water
- 24what are the disadvantages of quarrying limestone?dust
noise
traffic
loss of habitat for wildlife - 25what are the advantages of quarrying limestone?more employment
more customers for local businesses
improved roads - 26What is an ore?rock that contains metal or a metal compound
- 27what is displacement?metals which are less reactive than carbon can be extracted from their oxides by heating with carbon
- 28what is reduction?when carbon removes the oxygen from the oxide to produce the metal
- 29why does iron from the blast furnace have only a few uses?it has impurities which makes it hard and brittle
- 30how can iron from the blast furnace be made pure?by removing the carbon and other impurities
- 31what are steels alloys?they are a mixture of iron with carbon and other elements
- 32what are low carbon-steels?they are steels that can be easily shaped
- 33what are high-carbon steels?they are steels that are hard
- 34why can't aluminium be reduced?it is high in the reactivity series, and is more reactive that carbon
- 35why is it expensive to extract aluminium?it has to be extracted through electrolysis at high temperatures and uses a lot of electricity
- 36what are the two stages of extracting copper from copper-rich ores?smelting and purifying
- 37what is the process of smelting?heating the copper-rich ore strongly in a furnace
- 38what is the process of purifying?using electrolysis to purify the impure copper
- 39why are scientists trying to find new ways of extracting copper?smelting and purifying take up a he amount of heating and electricity
- 40what is phytomining?uses plants to absorb copper compounds, the plants are burned and produce ash from which copper can be extracted
- 41what is bioleaching?uses bacteria to produce solutions containing copper compounds
- 42how can we separate a mixture of liquids?dstillation
- 43what are fractions?distillation of crude oil that produces liquids that boil within different temperature ranges
- 44what are hydrocarbons?their molecules contain only hydrogen and carbon
- 45what is the process of fractional distillation?1. the crude oil is vaporised and fed into a fractionating column
2. the hydrocarbons condense to liquids when they reach their level that is at their boiling point
3. different liquids collect on the trays at different levels - 46what are the properties of fractions with low boiling points?low viscosity
flammable
burn with little smoke - 47what happens when pure hydrocarbons burn completely?they are oxidised to carbon dioxide and water
- 48what happens when incomplete combustion takes place?carbon monoxide is produced, also all the hydrocarbons may not have been burnt producing soot and particulates
- 49what does sulphur dioxide cause?acid rain
- 50what does carbon dioxide cause?global warming
- 51how do particulates effect the environment?particulates reflect sunlight and causes global dimming
- 52how can we remove waste gases before they are released into the atmosphere?- sulphur dioxide is removed in power stations
- exhaust systems are fitted with catalytic converters to remove carbon monoxide an nitrogen oxide
- filters can remove particulates - 53what are biofuels made from?plant or animal products
- 54what can biodiesel be made from?vegetable oils extracted from plants
- 55what are the advantages of using biodiesel?- little contribution to carbon dioxide levels
- 56what are the disadvantages of using biodiesel?- the plants grown for biodiesel use large areas of farmland
- 57advantage of using hydrogen as a fuel?- it produces only water when it is burned
- 58disadvantage of using hydrogen as a fuel?- takes up large volumes, making it difficult to store
- 59what is cracking?large hydrocarbon molecule that are broken down into smaller molecules
- 60which two ways can cracking be done?- by heating a mixture of hydrocarbon vapours steam to a very high temperature
- by passing hydrocarbon vapours over a hot catalyst - 61what are alkanes?they are saturated hydrocarbons
- 62what are alkenes?they are unsaturated hydrocarbons
- 63what bonds do alkenes have?double bonds
- 64what are plastics made of?very large molecules called polymers
- 65what are the small molecules that make up polymers called?monomers
- 66what is a shape memory polymer?polymers that change shape when temperature or other conditions are changed?
- 67what are two medical uses for polymers?- dental fillings
- plasters - 68what are two non-medical uses for polymers?- fabrics
- drink bottles - 69what does it mean by polymers non being biodegradable?the plastic waste is not broken down when left in the environment
- 70two ways that corn starch can be used to help with problems of disposal of plastic waste?- microorganisms break down the corn starch so the plastic breaks down into very small pieces and can be mixed with soil
- polymers made from corn starch can be used as food packaging - 71how can ethanol be produced?by the process of fermentation, enzymes in the yeast cause the sugar to convert to ethanol and carbon dioxide
- 72what is another way that ethanol can be produced?by the process of hydration of ethene, ethene is reacted with steam at high temperature in the presence of a catalyst. the ethene is obtained from crude oil by cracking
- 73what are the advantages and disadvantages of fermentation?Advantages:
- room temperature
- renewable
disadvantages:
- only produces a dilute aqueous solution - 74what are the advantages and disadvantages of ethene?advantages:
- can be run continuously
- produces pure ethanol
disadvantages:
- non-renewable
- high temperature - 75what two methods are used to extract vegetable oils?- by crushing and pressing the plant material, followed by removing water and other impurities.
- by distilling the plant material mixed with water, which produces a mixture of oil and water from which the oil can be seperated - 76why are vegetable oils important foods?- they provide us with energy and important nutrients
- they also release a lot of energy when they are burnt so they are used as fuels - 77why are some vegetable oils described as unsaturated?they have carbon-carbon double bonds
- 78why are foods from fast food outlets cooked in oil?the boiling point of vegetable oil is higher than water, so the food is cooked at higher temperatures and is cooked faster
- 79what is an emulsion?the mixture of oil and water together
- 80how can you recognise an emulsion?emulsions are opaque and thicker
- 81name some types of emulsions?Milk, Cream, Ice cream, Salad dressing
- 82what is an emulsifier?an emulsifier is a substance that that help stop oil and water from separating into layers
- 83describe an emulsifier molecule?the head of the emulsifier is hydrophilic (attracted to water) and the tail is hydrophobic (attracted to oil)
- 84give benefits and drawbacks to eating foods containing vegetable oils?benefits:
- high in energy
- contain nutrients
drawbacks:
- food likely to have high fat content - 85describe the structure of the earth?atmosphere
crust
mantle
core - 86what causes the tectonic plates the move?convection currents in the mantle
- 87how do earthquakes and volcanoes occur?when tectonic plates move and meet each other changing shape and moving suddenly
- 88what was the Wegener's theory?he put the idea of continental drift that was not accepted for years because of the lack of evidence
- 89what was the earths early atmosphere like?the earths atmosphere contained carbon dioxide, water vapour and nitrogen from volcanoes on the earths surface
- 90what produced the oxygen in the earths atmosphere?plants that evolved on the earth used the carbon dioxide for photosynthesis and released oxygen
- 91what was the Miller- Urey experiment?they used a mixture of water, ammonia, methane, and hydrogen and a high voltage spark to stimulate lightening. after a week they found out that amino acids had been produced
- 92how did carbon become locked up?plants took in carbon, the plats were eaten by animals and then dies which left the carbon locked up in sedimentary rocks and fossil fuels
- 93how can gases in the air be separated?by fractional distillation
- 94name processes that releases carbon dioxide into the atmosphere?- respiration
- combustion
- decay - 95name processes that remove carbon dioxide from the atmosphere?- photosynthesis
- dissolving in the ocean - 96which human activity is the man reason behind the increase in carbon dioxide levels?burning fossil fuels
Information
- Description
- A levels science (chemistry) Flashcards on chemistry 1, created by Alisha Khalid on 18/01/2015.
- Created by
- Alisha Khalid · Jan 2015
- Updated
- Apr 6, 2018
- Views
- 4
- Rating