midterm Flashcards
How do you write 0.00042 in scientific notation?
4.2x10^-4
How are science and technology related?
yes bc if technology advances so does science
What physical properties of nylon make them good shoe laces
flexible and durible
WHo provided evidence for the existence of the nucleus in an atom?
Rutherford
What characteristic of an element makes an element?
number of protons
what is flammibility?
ability to burn in the presence of oxygen
what does the electron cloud model describle about electrons
locations of electrons around nucleus
what is an atomic mass unit
1/12 mass of a carbon 12 atom
what happens to the number of valence electrons of an elementas you move left to right across a period in the periodic table
increases
what gives an element the tendency to react
number of valence electrons
how many valence electrons does Boron? helium?
Boron has 3, Helium has 2
which element is founf in most compounds in your body
carbon
what is an ionic bond
transfer of electrons
potassium, K, reacts w bromine, Br, to form what compound
Potassium Bromide
what is precision
exact
what is the slope of a line
vertical to horizantal change
where is chemical energy contained in a compound
in the bonds
what do reaction rates not tell you about a reaction
substances changing states
is celery considered acidic or basic
basic
on the ph scale what is 6 considered as
basic
strong electrolytes would be considered as what type of acids/basics
strong
what is a homo mix
remains evenly mixed, same
descrobe the shape and volume of liquid, solid, gas
def shape vol, gas indef
what is the grp name of the elements highest in reactivity
alkali metals (1A)
