Chapter 2: Chemistry Comes Alive Flashcards
Matter
Anything that occupies space and has mass
Energy
The capacity to do work, or to put matter in motion
Kinetic Energy
Energy in action
Potential Energy
Stored energy
What is the connection between matter and energy?
They are inseparable; Matter is substance and energy is the mover of the substance
Chemical Energy
The form stored in the bonds of chemical substances
1) Atoms rearrange
2) PE is released
3) KE
Describe Eating
1) Food E is captured temporarily in the bonds of a chemical called ATP
2) ATP bonds are broken, PE is released for cellular work
Electrical Energy
Results from the movement of charged particles
- Electrical currents (ions move across cell membranes)
- Nerve impulses
- Pumping blood
Mechanical Energy
Energy directly moving matter
Radiant Energy/ Electromagnetic Radiation
Energy that travels in waves
Electromagnetic Spectrum
Waves that are varied in length
Energy Conversions
- Energy can easily convert
- Inefficient: Initial energy is always “lost” in the environment as heat (unusable energy)
- All conversions give off heat: helps with homeostasis
Elements
Unique substances that cannot be broken down into simpler substances by ordinary chemical means
Atoms
Identical particles or building blocks of elements
Physical Properties
Those we can detect with our senses or measure
Chemical Properties
Pertain to the way atoms interact with other atoms
Nucleus
(1) Control center of a cell; contains genetic material; (2) center of an atom; contains protons and neutrons
Protons
Positive electrical charge
Neutron
Neutral, so nucleus is positive overall
What are the connections between protons, neutrons and the nucleus
1) Protons and neutrons are heavy subatomic particles of the nucleus
2) Nucleus is dense= 99.99% mass of the atom
Electrons
Negative charge equal in strength to the positive charge of the proton
What are all atoms charged?
Neutral; the # of protons in an atom is balanced by its # of electrons
Planetary Model
A simplified model of atomic structure
Orbital
Regions around the nucleus in which a given electron or electron pair is likely to be found most of the time