Chemistry

Atoms

All substances are made from atoms
Element: a substancs made from only one sort of atom
Groups in the periodis table contain similar properties
atoms have a nucleus made of protons and neutrons and around which there are electrons
Charges: Proton = +1. Neutron = 0. Electron = -1
The number of electrons is the same as the number of protons in the nucleus
Atoms have no overall electric charge
The number of protons is its atomic number. Protons + Neutrons = the atomic mass number

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Elements in the same group have the same number of electrons in their highest energy level (outer electrons) and this gives them similar chemical properties.
The elements in Group 0 are the noble gases. they're unreactive because their atoms have stable arrangements of electrons.

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Environmental. Economic. Social
Advantages of quarrying limestone
Limestone is a valuable natural resource that is used to make a number of building materials
Limestone quarries provide jobs for people which can boost the economy in the area
Quarries maintain and build new roads for transportation, making the area more accessible
Disadvantages of quarrying limestone
There is an increased level of traffic and noise pollution in areas with quarries because of the amount of lorries needed to transport the limestone
Quarrying limestone produces lots of dust which will affect the health of people in the area
Quarries scar the landscape and ruin the look of the countryside

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