Jhaque

Why do ionic compounds conduct electricity when molten or dissolved? Because the ions are free to move and carry charge. What is covalent bonding? Sharing of electrons between two non-metal atoms. Do covalent compounds conduct electricity? Why? No, because they don't have free charged particles. What is metallic bonding? Positive metal ions surrounded by a sea of delocalized electrons. Why are metals good conductors of electricity? Because the delocalized electrons in...

What color flame test for calcium go? Yellowy red What color flame test for copper go? Blue/ Green. What happens when you react aluminum with sodium hydroxide? White precipitate forms. Which dissolves in excess. What happens when you react calcium with sodium hydroxide? White precipitate forms. What happens when you react magnesium with sodium hydroxide? White precipitate forms. What happens when you react copper (II) with sodium hydroxide? Blue precipita...

NPK fertilizers use and makeup These are formulations made to improve agricultural productivity. They are made of salts of: - Nitrogen - Phosphorus - Potassium How to get nitrogen for NPK fertilizers Ammonia, produced in the Haber process, can react to form other nitrogen-containing compounds, e.g. reacting ammonia with oxygen and then water produces nitric acid. Ammonium salts are common compounds found in fertilisers - formed by reacting ammonia with acids. Ammonium nitrate is a use...

Burning fossil fuels releases more CO2 Agriculture farm animals produce methane Creating waste - landfills waste contributes to CO2 build up Climate change consequences ice caps melt animals die weather changes temp changes Carbon footprints measure of the amount of greenhouse gases released by something over its lifetime. Air pollution pollutants: fossil fuels incomplete combustion - soot carbon monoxide release of sulfur dioxide and oxides of nitrogen ...

Electroplating coating (a metal object) by electrolytic deposition with chromium, silver, or another metal. Carat a measure of the purity of gold, pure gold being 24 carats. Steels alloys of iron with carbon and/or other elements Carbon steels the simplest steels, alloys of steel with carbon. Stainless steels chromium-nickel steels that combine hardness and strength with great resistance to corrosion. Thermosoftening polymer polymers that soften when heated and har...

What is the advantage of borosilicate glass over soda-lime glass? Borosilicate glass melts at a higher temperature Give two examples of clay ceramics Pottery and bricks How are clay ceramics made? By shaping wet clay and then heating in a furnace What do the properties of polymers depend upon What monomers the polymer is made from and the conditions under which they are made Name the two polymers made from ethene Low density poly(ethene) (LDPE) and high density poly(ethe...

Why must the anode be replaced regularly? The anode must be replaced regularly because the oxygen produced at the anode reacts with the carbon in the graphite forming carbon dioxide gas What are exothermic reactions? Exothermic reactions are reactions that transfer energy to their surroundings What happens to the temperature of the surroundings in an exothermic reaction? In an exothermic reaction the temperature of the surroundings gets increases Give three examples of exotherm...

THIS EXAMS COVERS AQA GCSE AND AQA A LEVEL BIOLOGY EXAMS PAPERS 1 AND 2.

Write a paragraph using the terms probability and chance if the different or association from stats results at P 0.001 has a calculated value greater than the criterial value. The probability of the difference or association being due to chance is less than 0.1% ; Therefore, there is a significant difference or association between the two means/variables Describe how you would calculate dry mass Heat at 100°C / heat to temp to evaporate water; Weigh and heat until no further change in ma...

What are photosynthetic organisms? Producers of biomass for life on Earth What is a food chain? A feeding relationship within a community What is a producer? An organism that synthesises molecules Give an example of a producer A green plan or alga that make glucose by photosynthesis What is a primary consumer? An organism that eats a producer What is a secondary consumer? An organism that eats a primary consumer What is a tertiary consumer? An organism that e...