Chemistry in Society Flashcards
What is metallic bonding?
The electrostatic force of attraction between positively charged ions and delocalised electrons
What is the word equation for a reaction between a metal and oxygen?
metal + oxygen –> metal oxide
What is the word equation for a reaction between a metal and water?
metal + water –> metal hydroxide + hydrogen
What is the word equation for a reaction between a metal and a dilute acid?
metal + dilute acid –> salt + hydrogen
What is reduction?
the gain in electrons
What is oxidation?
the loss of electrons
What is a redox reaction?
a reaction in which reduction and oxidation take place at the same time
What metals are extracted using only heat?
Silver, gold and mercury
What metals are extracted using carbon or carbon monoxide?
Calcium, Lead and Zinc
What is electrolysis?
the decomposition of an ionic compound using electricity
At which electron will a positive ion gain electrons?
Negative
What happens to negative ions at the positive electrode?
They lose electrons
What are electrolytes?
solutions that conduct electricity
What are plastics?
materials known as polymers
What is addition polymerisation?
a chemical reaction in which unsaturated monomers are joined together to form a polymer
What are the nutrients that plants require to grow healthily?
Nitrogen, Phosphorus and Potassium
What does the stability of nuclei depend upon?
The proton to neutron ratio/balance
What are the three types of radiation?
alpha, beta, gamma
What is the charge on alpha particles?
2+
How are alpha particles stopped?
a few centimetres of air
What does alpha radiation consist of?
helium nuclei
2 2+
He
4
What is a beta particle?
an electron
0 -
e
1
What are gamma waves?
electronegative waves
What is half-life of a radioisotope?
the time taken for the sample’s activity to fall in half
What are some uses for radioisotopes?
To treat cancer, treat thyroid gland, to date once-living materials
Which radioisotope is found in every living organisms?
carbon-14
How is carbon-14 formed?
When neutrons from cosmic radiation collide with nitrogen atoms in the atmosphere forming protons and carob-14 atoms
Where does alpha decay take place most commonly?
In very large nuclei with too large a proton to neutron ratio
How does alpha decay affect the atomic and mass numbers of a radioisotope?
the atomic number will decrease by 2 and the mass number will decrease by 4
How does beta decay affect the atomic and mass numbers of a radioisotope?
the atomic number will increase by 1 and the mass number will be unaffected
How does gamma decay affect the atomic and mass numbers of a radioisotope?
neither will be affected
What is qualitative analysis?
used to find out if a substance is present in a sample
What is quantitative analysis?
used to find how much of a substance is present in a sample
Which kind of analysis are flame tests?
qualitative analysis
What is a precipitation reaction?
a reaction in which substances in a solution are mixed and an insoluble product