Chemicals In The Atmosphere Flashcards
Name three gases that are elements…
Nitrogen (78%)
Oxygen (21%)
Argon (1%)
What gas is a compound in the atmosphere ? (Chemically bonded together)
Carbon dioxide.
Most gases in the atmosphere are molecular. What are some features of molecular substances?
Small molecules such as H2O
Low melting/boiling point due to weak intermolecular forces.
Mainly liquids and gases at room temperature.
Strong covalent bonds - they do not conduct electricity as the atoms are not charged.
How does covalent bonding work?
Electrons are shared between atoms to complete the outer shells for both, making them stable.
One covalent bond =
One pair of electrons shared.
What holds atoms together in covalent bonds?
Electrostatic attraction between electrons and positive nuclei.
Carbon dioxide has …
Two double covalent bonds (two pairs of shared electrons).
What is oxygen’s molecular formula and displays formula?
O2, and O=O. For a 3D formula draw two circles and two lines to show the double bond.
Dry air is a mixture of…
Gases.
