Quiz 1: 1.1-1.5 Flashcards
chemistry
the study of matter and how it changes
matter
anything that has mass and takes up space
atom
smallest part of an element that is still that element
molecule
two or more atoms joined & acting as a unit
chemical reaction
one substance changes to another by reorganizing the way the atoms are attracted to each other
measurement
quantitative observation consisting of two parts:
- number
-scale (unit)
kilogram (kg)
SI mass unit
meter (m)
SI length unit
second (s)
SI time unit
kelvin (K)
SI temperature unit
mole (mol)
SI amount of substance unit
kilo (k)
1,000 or 10^3
deci (d)
0.1 or 10^-1
centi (c)
0.01 or 10^-2
milli
0.0001 or 10^-3
nonzero integers
always count as significant figures
leading zeroes
never count as significant figures
captive zeroes
always count as significant figures
trailing zeroes
significant only if the number contains a decimal point:
9.300 has 4 sig figs
150 has 2 sig figs
exact numbers
infinite number of significant figures
multiplication/division & sig figs
the number of significant figures in the result is the same as the number in the least precise measurement used in the calculation
addition/subtraction and sig figs
the result has the same number of decimal places as the least precise measurement used in the calculation
meniscus
bottom of the liquid curve where the volume is read
accuracy
agreement of a particular value with the true value
