Chapter 2 - Reaction Types Flashcards
Reactants in chemical equation
Come before the arrow. They react to form the products
Law of conservation of matter
Matter cannot be created or destroyed
Balanced equations and law of conservation matter
Obviously if matter cannot be created or destroyed, in chemical equations they must be balanced to show the law of conservation of matter
Isotopes
Different atoms of the same element. They have the same number of protons but a different number of neutrons
Radioisotope
Some isotopes are unstable. These are called radioisotopes. They decay over time and release energy (nuclear radiation)
Half life
The time taken for half if the substance to decay into other ato,s. Different radio isotopes have different half lives. Eg: Potassium-42 = 12 hours, Uranium-235 = 703.2 million years
Products in chemical equation
Come after the arrow
Types of Nuclear Radiation
Alpha, beta, gamma
Alpha Diagram
2 neutrons and 2 protons
Alpha description
2 protons and 2 neutrons. Nucleus of a helium. Moves towards negative in a magnetic field
Alpha charge
+2 positive
Penetration alpha
Stopped by 6cm of air, paper, easily stopped
Ionising strength alpha
High 20 electrons over alpha particle
Beta diagram
1 electron
Beta description
An electron. Moves towards positive in magnetic field
Beta charge
-1 negative
Penetration beta
Stopped by aluminium
Ionising strength beta
Medium 1 electron per beta particle
Gamma diagram
A wave
Gamma description
Wave with no mass. Electromagnetic wave, not effected by magnetic field. Also nuclear radiation
Charge gamma
No charge
Penetration gamma
Stopped by 10cm of lead. Hardest to stop
Ionising strength gamma
Low 1 electron per gamma ray
Nuclear Radiation
Any rays or particle emitted by atomic nuclei
Ionising radiation
Can remove electrons from atoms and molecules causing them to die or mutate
Radiation burns
Cause by short exposure to large amounts of radiation. Damages cells on surface causing blistering, redness and itching
Radiation sickness
Caused by short exposure to large amounts of radiation or long exposure to small amounts of radiation. Causes nausea, vomiting, fever, hair loss, diarrhoea
Cell mutation
If radiation damages DNA (which tells the cell how to function), the the cell is reprogrammed and a cancer can grow eg: melanoma. This can happen from even small exposure but the likelihood of it happening increases with exposure to radiation. Ionising radiation can also cause mutation in sperm and ova causing genetic or inherited mutation in offspring. This usually occurs in animals, not humans
Useful radiation - Radiotherapy
Radiotherapy is used to treat cancers. The cancer is exposed with a high concentration of radiation to kill the cancer cells. But this can come with side effects by also killing so,e healthy cells and resulting in nausea, hair loss, heart disease etc
Useful radiation - sterilisation
Radiation is also used to kill bacteria in medical equipment and food. Eg: bandages and needles can be sterilised without the use of harmful chemicals. Food treated with radiation lasts longer before rotting or going stale
Complete methane combustion equation
Methane + oxygen gas —> Carbon dioxide + water vapour
Complete octane combustion reaction
Octane + oxygen gas —> Carbon dioxide + water vapour
Incomplete methane combustion equation
Methane + oxygen gas —> Carbon monoxide + water vapour
Acid carbonate word equation
Acid + Carbonate —> salt + water + carbon dioxide
Acid carbonate symbol equation
2HCl+CaCO3 —> CaCl3 + H2O + CO2
