Definitions
What is a compound?
Two or more different elements chemically bonded together
Which subatomic particles make up the nucleus of an atom?
Protons and neutrons
How many significant figures is in the following number:
5.091
4 sig figs
Convert 35 mm into m.
0.035 m
Who conducted the gold foil experiment?
Lord Ernest Rutherford
What is a reactant?
Elements or compounds that go into a chemical reaction
What would the charge of an atom be that contained 6 protons, 8 electrons, and 7 neutrons?
-2
How many significant figures is in the following number:
0.0380
3
Write the following number in scientific notation with two significant figures:
240000
2.4 x 10^5
What was the Greek word Democritus used to describe the tiny, indivisible particles that made up everything?
atomos
What is atomic number?
The number of protons in the atom of an element
What is JJ Thomson's model of the atom known as?
Plum pudding model
How many significant figures would be in the product of the following calculation:
2.87 x 1.023
3 sig figs
Convert 56.6 microseconds to milliseconds
0.0566 milliseconds
T/F
Electrons can travel outside of their orbitals
False
What is the difference between accuracy and precision?
Accuracy refers to the lack of error in a measurement while precision refers to the resolution, or degree of "fine-ness" in a measurement.
Who determined the mass and charge of an electron?
Robert Millikan
How many significant figures would be in the sum of the following calculation:
9.03 + 200.4 =
4 sig figs
Wiley expected to get a 95 on his chemistry test but he received a 63. What was his percent error?
33.7%
molecules and crystals
Describe electronegativity and give an example.
The tendency for an atom to attract electrons towards itself.
Ex. Oxygen pulls electrons closer to itself in a water molecule
Name any 3 tenets of Dalton's atomic theory.
1. All substances are made of indivisible substances called atoms.
2. All atoms of the same substance are identical
3. Atoms of different elements have different weights
4. Atoms combine in whole number ratios
5. Atoms are neither created nor destroyed in chemical reactions
How many significant figures would there be in the product of the following calculation:
(0.0051+7.82) x 2.2
2 sig figs
What is the solution to the following calculation in METERS, written in scientific notation with the correct number of significant figures:
200.803 km + 5.1 km =
2.059 x 10^5 m = 4 sig figs
Explain why accuracy is important on a heart rate monitor, but precision is not.
The heart rate monitor needs to accurately measure someone's heart rate, meaning that it is close to the real value; but it does not need to be precise because there is no real difference between 120 bpm, 121 bpm, or even 125 bpm and there is no need for more significant figures, such as 123.8 bpm.