CHEM 2100 EXAM question with answers
Element - -: sub that can not be broken down into simple sub
-Compound - -: sub composed of 2 or more diff elements
-Atoms - -are single neutral particles.
-Molecules - -Groups of two or more atoms held together by chemical bonds
-ion - -is a positively or negatively charged particle
-Homogenous - -uniform throughout
-Heterogeneous - -nonuniform, vary in texture and appearance
-Physical properties - -unchanging identity and composition
-Chemical properties - -property describes how a sub may change or react to form
another substance
-intensive property - -Independent on the amt of substance involved
-extensive property - -a property that depends on the amount of matter in a sample
-Accuracy - -how close individual measurements are to the "true" value
-Precision - -how close individual measurements are to one another
-Significant Figures - -All non-zero numbers ARE significant. ...
Zeros between two non-zero digits ARE significant. ...
Leading zeros are NOT significant. ...
Trailing zeros to the right of the decimal ARE significant. ...
Trailing zeros in a whole number with the decimal shown ARE significant
-Conversion factor - -a fraction whose numerator and denominator are the sane
quantity expressed in different units
-Dalton's Atomic Theory - -Each element is composed of extremely small particles
called atoms
All atoms of a given element are identical, but the atoms of one element are different
from the atoms of all other elements
Atoms of one element cannot be changed into atoms of a different element by chemical
reactions: atoms are neither created nor destroyed in chemical reactions
Compounds are formed when atoms of more than one element combine; a given
compound always has the same relative number and kind of atoms
-conservation of matter - -the total mass of materials present after a chemical
reaction is the same as the total mass before the reaction
Element - -: sub that can not be broken down into simple sub
-Compound - -: sub composed of 2 or more diff elements
-Atoms - -are single neutral particles.
-Molecules - -Groups of two or more atoms held together by chemical bonds
-ion - -is a positively or negatively charged particle
-Homogenous - -uniform throughout
-Heterogeneous - -nonuniform, vary in texture and appearance
-Physical properties - -unchanging identity and composition
-Chemical properties - -property describes how a sub may change or react to form
another substance
-intensive property - -Independent on the amt of substance involved
-extensive property - -a property that depends on the amount of matter in a sample
-Accuracy - -how close individual measurements are to the "true" value
-Precision - -how close individual measurements are to one another
-Significant Figures - -All non-zero numbers ARE significant. ...
Zeros between two non-zero digits ARE significant. ...
Leading zeros are NOT significant. ...
Trailing zeros to the right of the decimal ARE significant. ...
Trailing zeros in a whole number with the decimal shown ARE significant
-Conversion factor - -a fraction whose numerator and denominator are the sane
quantity expressed in different units
-Dalton's Atomic Theory - -Each element is composed of extremely small particles
called atoms
All atoms of a given element are identical, but the atoms of one element are different
from the atoms of all other elements
Atoms of one element cannot be changed into atoms of a different element by chemical
reactions: atoms are neither created nor destroyed in chemical reactions
Compounds are formed when atoms of more than one element combine; a given
compound always has the same relative number and kind of atoms
-conservation of matter - -the total mass of materials present after a chemical
reaction is the same as the total mass before the reaction
