Elements Flashcards
(18 cards)
What is a compound?
A compound is when 2 or more elements combine. E.G: Oxygen and Carbon make carbon-dioxide. When two or more elements are combined it is called
‘Chemically Bonded’.
What is an Element?
Elements are substances and they are made up of one kind of atom. Hydrogen is an Element. Cannot be broken
What is a Mixture?
A mixture is when 2 or more substances that are mixed together but are not chemically bonded.
Name 5 different fuels
Petrol, gas, coal, oil and wood
What is combustion?
Combustion is a scientific word for burning. We need oxygen to burn something. Most fuels are hydrocarbons.
What is a fuel?
A fuel is a material such as coal and gas. Fuel also gives power to a vehicle. It also causes fire to burn fiercely.
Oxides
When substance burns and reacts with oxygen the new substances formed are called ‘oxides’
Exothermic
When fuels burn they react with oxygen. This reaction releases energy. The reaction is exothermic. The energy content foods and fuels can be measured using calorimeter
Aerobic
Aerobic respiration is when glucose and oxygen combine together in cells to produce water and carbon dioxide which release energy. This is known as aerobic respiration because oxygen plays the most important role in order for this work
What is fossil fuels?
A natural fuel such a goal and gas.
How many groups are there in a periodic table?
There are 7 groups
What is an alkali?
An alkali is a compound that dissolves to give a solution with a pH higher than 7.
What is respiration?
The meaning of Respiration is when a chemical reaction happens. This happens in all living cells and plant and animal cells. Respiration is when energy is released from Glucose.
What happens if you add Glucose and Oxygen together?
If you add glucose and oxygen together, it makes a combination of carbon dioxide plus water.
What is an atom?
Everything is made from atoms, including you. Atoms are tiny particles that are far too small to see, even with a microscope.
Elements
Each element is given its own chemical symbol, like H for hydrogen or O for oxygen. Chemical symbols are usually one or two letters long. Every chemical symbol starts with a capital letter, with the second letter written in lower case. For example, Mg is the correct symbol for magnesium, but mg, mG and MG are wrong
Formula and Formulae
The word ‘formulae’ is the plural of ‘formula’. If we have more than one formula, we don’t say formulas, we say formulae.
The formula for a substance is always the same
All compounds have a definite composition. For example, a water molecule always contains two hydrogen atoms and one oxygen atom. It cannot be a water molecule if it has different numbers of these atoms. The formula for water is always H2O.
