Radioactivity
Radiation with least penetrating power
alpha particle
The time required for half the atoms in a sample of a radioactive nuclide to undergo decay
Half-Life
The conversion of atoms of one element to atoms of another.
Transmutation
large molecules made of many small units joined together
What is a Polymer?
energy source for photosynthesis
Energy from the sun
The spontaneous disintegration of a nucleus into a slightly less massive and more stable nucleus, along with emission of particles or radiation or both
Radioactive Decay
What percentage of the original amount of carbon-14 remains in a 20 g sample after two half-lives?
25%
Elements with more than 92 protons in their nuclei.
Transuranium Elements
Natural Polymers
What are cellulose, starch and glycogen?
Type of radiation where there's No change in mass and no change in charge
gamma rays
Electron emitted from a nucleus
Beta particle
16 gm sample of a radioactive element is left for 2 hours and it was found that 1 gm of the element remained
Calculate the fraction left and how many Half lives have passed
16 --> 8 --> 4 --> 2 --> 1
4 half lives have passed
1/2 x 1/2 x 1/2 x 1/2 = 1/16
Scientists can synthesize a transuranium element by________________________
artificial transmutation of lighter elements
molecules that contain 3000 or more glucose monomers
What is cellulose?
products of photosynthesis
oxygen and glucose
Radiation with most penetrating power
Gamma rays
The half-life of Cobalt-60 is 5.3 years, what's the fraction of a sample remaining after 10.6 years and the amount of grams remaining if starting amount is 20 grams
1/4
5 grams
These are used to study the structure of the atomic nucleus, they cause collisions of particles near the speed of light
particle accelerators
monomers that make up proteins
Amino acids
products of cellular respiration
water and carbon dioxide
Used in Radioactive dating
Carbon-14
a radioisotope has a half life of 1600 years. How much will remain from a sample of 10 grams after 3200 years?
3200 / 1600 = 2 half lives have passed
10 --> 5 --> 2.5 grams
During Nuclear decay the atoms of one element can change into atoms of a different element. T/F
True
The strands of DNA are held together in the double helix by these forces
Strong intermolecular forces of attraction
substances that allow reactions to occur at lower temperatures than normal.
Enzymes