term 1 test study Flashcards
what is chemical change?
chemical change is any change that results in the formation of a new chemical change.
what is physical change?
substances that undergo change, that makes them have a dramatic difference in appearance but the chemical composition of the substance stays the same. eg you rip a piece of paper but it is still paper, it just appears different
how are physical and chemical changes different?
the difference between physical and chemical changes are if you change something physical you still have the same substance as you’ve started with eg if you rip paper but with chemical changes it changes
polymers?
a substance which has a molecular structure built up chiefly or completely from a large number of similar units bonded together, e.g. many synthetic organic materials used as plastics and resins.
what is a natural polymer
cotton, natural rubber, starch
what are synthetic polymers?
plastic, synthetic rubber and other synthetic fibres
monomers?
a molecule that combine of the same kind to form a polymer
molecule?
a group of atoms bonded together, representing the smallest unit of a chemical compound
atom?
a basic unit of an element and a form of matter that can not be broken down.
biodegradable?
capable of being composed by bacteria or living organisms
biodegradable plastic?
plastic capable of be composed, if it is made from substances that can decompose eg starch, cellulose, biopolymers
independent variable?
what we change deliberately
dependent variable?
what has changed due to the effect of what we change
control variable?
some thing that is constant and unchanged eg watering a plant
