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Calculations
Atoms
Periodic Table
Pure Substances & Mixtures
Periodic Trends
100
A liquid is measured five different times and each time 47 ml is recorded as the measured amount. The actual measurement is 82.1 ml. In terms of precision and accuracy the measurements are:
Precise but not accurate
100
What is the difference between mass number and atomic mass?
Mass number is an atom's protons plus its neutrons. Atomic number is average mass of an element considering the relative abundance of all of its isotopes.
100
How many electrons in Phosphorus
15
100
A phase change from gas to liquid is called:
condensation
100
On the periodic table, what are the trend directions for atoms that have increasing electronegativity (choices: left to right, right to left, top to bottom, or bottom to top)?
From left to right and bottom to top
200
The length of a paper clip is measured with a ruler that has increments for both centimeters and millimeters. The clip is determined to be between 2 cm and 3 cm. Choose the correct measurement: 2.30 cm, 2.3 cm, 2.300 cm
2.30 cm
200
If the mass of two atoms (12.011 moles and 24.30 moles) are multiplied together, their product will contain how many significant figures?
4
200
A Fluorine atom would most likely form an ionic bond with atoms in which Group?
Group 1
200
Systems that gain heat energy, such as water brought to a boil, are known as ________ reactions.
endothermic
200
On the periodic table, what are the trend directions for atoms that have increasing ionization energy (choices: left to right, right to left, top to bottom, or bottom to top)?
From left to right and bottom to top
300
Convert 2237 centiliters to hectoliters (1 hectoliter = 10,000 centiliters)
0.2237 hectoliters
300
How are isotopes of an element different from one another?
have different number of neutrons
300
How many neutrons are in Carbon-14?
8
300
Pure substances are either _________ or ________.
elements or compunds
300
On the periodic table, what are the trend directions for atoms that have increasing atomic radius (choices: left to right, right to left, top to bottom, or bottom to top)?
From right to left and top to bottom
400
If you are running at 8 miles per hour, what is your speed in meters per second (1 mile= 1.61 kilometers, 1 kilometer= 1000 meters, 3600 seconds= 1 hour)?
3.58 m/s
400
How do the masses of the subatomic particles compare to one another?
Protons and neutrons have almost identical masses and are much heavier than electrons.
400
In addition to having similar chemical characteristics, atoms in the same Group also have identical (2 things):
valence number and oxidation number
400
Molecules are non-metal atoms that are bonded together covalently, and they are either non-polar (share electrons equally) or polar (do not share electrons equally and thus have positive and negative regions). Give an example of a polar molecule.
H2O
400
Positive ions are called _________ and negative ions are called _______.
cations; anions
500
What is the molecular geometry of H2S?
Bent
500
SO4 2- has how many octet electrons?
40
500
Aluminum must _____ (gain/lose) ______ (how many) electrons to achieve a noble-gas electron configuration.
lose three electrons
500
Describe intensive and extensive physical properties and give an example of each.
extensive (depends upon amount of matter present): mass, volume, length, weight, height) intensive (does not depend upon the amount of matter present): color, density, conductivity, melting point)
500
In ionic compounds electrons are _____ and the atoms consist of _____ and _____. In covalent compounds electrons are _____ and the atoms consist of ______ and _____.
Ionic compounds: electrons transferred; metals and non-metals Covalent compounds: electrons shared; non-metals and non-metals