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Houses in the Inner City were normally built in the Victorian era/ pre WW1 and so reflect the requirements of housing at these times. They are normally terraced houses located on long, straight roads in a grid system, with small gardens so to fit as many houses as possible into a small space. In most cases, these houses will open straight out onto the pavement, with minimal front gardens. Houses could be 3 or even 4 stories tall, so to accomodate multiple families during the rural-urban migrations occuring during the industrial revolution.
In contrast, suburbian housing was built post- WW2 up to the present day, where requirements were very different. 2 story, detached and semi-detached houses were more fashionable at these times as people searched for a "happy medium" between city and country. As such, suburban houses are more widely spaced, with larger gardens, parks nearby and wider streets (usually with "closes" and dead-end roads). Houses are normally larger (though not universally so) but most certainly have larger rooms. Driveways and garages allow for greater car-ownership during this period.see more
CFC's (Chloroflourocarbons) are pretty inert at ground level, but can harm the Ozone layer in the Stratosphere by catalysing it's destruction.
In the first stage, a CFC reacts with UV radiation to form a Chlorine Radical (which has an unpaired electron).
CCl2F2 + UV --> CClF2 + Cl*
In the second stage, that Chlorine Radical reacts with Ozone to produce Oxygen Gas and Chlorine Oxide.
Cl* + O3 --> O2 + *ClO
This is the actual destruction of Ozone. However the real problems are caused by the next stage.
In stage 3, ClO reacts with an Oxygen radical to produce more Oxygen gas and the initial Chlorine Radical.
*ClO + *O* --> O2 + Cl*
It reacts with Ozone (it just depends on which it happens to collide with in the atmosphere). The Chlorine Radical is still reformed this way.
*ClO +O3 --> 2O2 + Cl*
As you can see, the Clorine Radical doing all the damage is regenerated. This means that one CFC molecules can destroy lots of Ozone and this is why the issue is so vast.see more
Sodium Chloride is an ionic compound which, when formed, exists as a 3D giant "cube based" ionic lattice with 6-6 coordination. In this lattice, each sodium ion (positive ion) is surrounded by 6 chlorine ions (negative ions) to which it is ionically bonded. The sodium ion is attracted to the chlorine ion by electrostatic forces (caused by opposing charges).
In contrast, Diamond is a covalently bonded form of Carbon in the form of a 3D giant tetrahedral covalent structure. Each carbon atom is covalently bonded to 4 other carbon atoms and there are no charges or ions. The covalent bonds are formed by the donation of an electron from each atom to form a pair of electrons. These electrons are attracted to the positive nuclei of both bonding atoms, holding them together.
So in conclusion:
Sodium Chloride is: an IONIC LATTICE, based around a series of CUBES, with 2 DIFFERENT ELEMENTS- Sodium and Chlorine. Each ion is bonded to 6 others.
Diamond is: a COVALENT LATTICE, based around a TETRAHEDRAL STRUCTURE, with only 1 ELEMENT involved (Carbon). Each atom is bonded to 4 others.see more