pH Lab (1) Flashcards
Scientific Method
observations that lead to a general question addressed by experimentation
Hypothesis
making predictions and must be testable
Null Hypothesis
it states there is no difference in treatment and control group
Theory
supported by evidence
Law
proven idea
Alternative Hypothesis
variable had an effect on the outcome of the experiment
Standard Deviation
square root of variance (s)
Standard Error
shows how much variation is associated with the mean
SE= st.dev /sqrt n
Variance
measure of distribution of data (s^2)
S^2=sum of indv observed-mean ^2 / n-1
T-test
type of analysis used to compare two sample means
Mean
experimental/arithmetic average of data
pH
hydrogen ion concentration
-log[H+]
pH of 7 only neutral with pure water @ 25 deg celcius
Acidic Solution
donation of protons
higher concentration of H+ ions than OH (hydroxyls)
pH is less than 7
Basic Solution
acceptance of protons
higher concentration of OH than H+ ions
pH is greater than 7
Buffers
weak acids or bases that react with strong acids or bases to prevent changes in pH
buffers keep pH neutralized, the same.
pKa buffers prevent the solution from becoming too acidic or too basic