Scientific Method
Chemistry
Chemistry 2 :)
I really love Chemistry
Water and Stuff
pH/Buffers
100
This step of the scientific method is usually proposed as an "if...then..." statement.
Prediction
100
What is the smallest unit of matter?
An atom
100
What is the name of an atom that is charged?
An ion
100
What are the three types of chemical bonds?
Polar covalent
Nonpolar covalent
Ionic
100
What is the difference between adhesion and cohesion?
Cohesion is the property of water sticking to another water molecule, while adhesion is the property of water sticking to a different molecule?
100
What is the formula used to find the pH when given the [H+]?
pH = -log[H+]
200
The following claim is an example of what part of the scientific method:
Blue light increases plant growth.
Hypothesis
200
The three subatomic particles that comprise an atom are ______, _______, and an _______.
Proton, neutron, electron
200
In any hydrogen atom, which of the subatomic particles will always be the same?
Protons
200
What type of chemical bonding is present in methane (CH4)?
Nonpolar covalent
200
What does it mean to have a high specific heat capacity?
You require a lot of heat to raise the temperature.
200
The pH of human blood needs to be maintained at a range very close to ____.
7.4
300
The ________ __________ is a method employed by posing multiple hypothesis then using deduction to eliminate poor explanations.
Hypothetico-deductive method
300
The mass of an atom is located in the ______, while most of the volume is located in the _______.
Nucleus
Electron Cloud
300
What is the relationship between protons and electrons in an atom containing a positive charge?
P>E
300
A negatively charged atom is called a _____.
Anion
300
What happens to the density and volume of water when the temperature is >4oC? What happens to the density and volume of water when the temperature is <4oC?
Density gets lower while volume gets higher.
300
What is the name of the buffer used to control pH in the human body, as well as it's ion?
Carbonic Acid
Bicarbonate Ion
400
Four groups of rats are first massed then fed identical diets, except for the amount of vitamin A they receive. Each group gets an increasing amount of vitamin A. After 3 weeks, the rats' masses are measured and compared.
Identify the independent variable and dependent variable.
IV - [Vitamin A]
DV - mass of the rats
400
What are the ion(s) important in bone formation?
Ca2+
400
Why is the atomic mass for each element on the periodic table NOT a whole number?
It is an average of the mass of all existing isotopes and their relative abundance in nature.
400
The product of ionic bonding is called a _____. These are attracted to form a ______.
salt
lattice
400
Name the 4 emergent properties of water.
Cohesion/Adhesion
High Specific Heat capacity
Expands upon freezing
Dissolves and dissociates
400
What is [H+] of a solution with a pH of 3?
10-3 M
500
What relationship does a line of best fit with a downward slope demonstrate?
Inverse Correlation
500
Propose a shell diagram for a Mg2+ ion.
500
How many valence electrons does a S atom have?
6
500
In a molecule of water, the ____ atom(s) will have a partial positive charge, while the _____ atom(s) will have a partial negative charge.
H
O
500
How many grams of NaCl does 500 mL of a 0.25 M solution contain?
7.305 g
500
What makes an acid such as HCl as "strong acid"?
It completely dissociates into it's ions: H+ and Cl- when put in an aqueous solution.
600
Which graph will have an r2 value closer to 1?
Left
600
Indicate how many of each subatomic particle is present in the following ion:
32P1-
Protons: 15
Neutrons: 17
Electrons: 16
600
What is the name of this ion:
Hydride ion
600
This type of bonding is characterized by the unequal sharing of electrons. What is an example of a molecule containing this type of bonding?
Polar covalent. Water or ammonia.
600
If I have 30g of KBr, what value do I need in order to find out how many moles of KBr I have?
The molar mass of KBr.
600
What kind of base is ammonia considered? What ion is created after association with an H+?
Bronsted-Lowry base.
Ammonium Ion = NH4+
700
What is the experimental variable in the following graph?
Age of drivers
700
What are the ion(s) important in oxygen transport? Muscle contractions?
Fe2+
Na+, K+, Ca2+
700
What are the 6 most abundant elements that make up the human body?
O, C, H, N, Ca, and P.
700
The physical bond involved in the dissociating of salts is called _______ ________.
Hydrogen Bonding
700
What does it mean to be an aqueous solution?
The solvent is water.
700
Acids _____ (attach/release) H+ in a solution, while bases ______ (attach/release) H+ in a solution.
Release
Attach