Unit 1/2
What’s the difference between a theory and a law?
A theory is something you predict while a law is a fact.
What is the equation for density?
Density=Mass/Volume
Who created the plum pudding model?
JJ Thompson
Who published the first table of elements?
Dimitri Mendeleev
What are ionic compounds physical structure?
All ionic compounds are crystal structures
T/F - Solid liquid and gas all have definite volume
False only solid and liquid do
What’s the difference between accuracy and precision?
Accuracy is a measure of how close something comes to an accurate value and precision is a measure of how close a series of measurements are to another.
What are isotopes?
Atoms that have the same number of protons but different number of neutrons
Difference between periods and groups?
Periods are the seven rows each with a principal of energy and groups are columns of the periodic table.
What is the difference between canions and anions?
Canions are positively charged when an atom loses one or more valence electrons and anions have a negative charge in produced when an atom gains one or more valence electrons
What are the four chemical changes?
Color, energy, gas, precipitate
Convert the following- 1.5kg=g?
1,500
Where are the protons, neutrons, and electrons located in the atom?
Protons-nucleus
Neutrons-nucleus
electron-around the nucleus
What element has full valence levels and is the least reactive?
Noble Gas
Do ionic compounds have high or low melting points?Why?
High-they are solids and it’s generally harder to melt liquid
What is the difference between a heterogeneous mixture and a homogeneous mixture?
In Heterogeneous the composition is not uniform and in Homogeneous the composition is uniform.
Calculate the volume of a liquid with a density of 5.45g/mL and a mass of 65.0.g
11.9mL
How do you calculate atomic mass?
1. Add together then divide by 2
2. Isotope mass times percent abudance
3.Percent abundance in decimal form
Place the following elements in order according to increasing atomic radius-Fr,Cs,Rb,Li,Na
Li,Na,Rb,Cs,Fr
Give the formula for this compound: aluminum sulfide
Al2S3
When you use a hammer and anvil to flatten the end of a copper wire what type of change would that be?
Physical Change
What is the formula for percent error?
(Experimental value - accepted value) divided by accepted value multiplied by 100
Difference between a Celsius Scale and a Kelvin Scale?
Celcius sets the freezing point of water at 0 degrees Celsius and boiling point at 100 degrees Celsius and Kelvin scale the freezing point is at 273.15 and the boiling point is 313.15
Which way does the electronegativity increase and decrease?
Decrease-Top to bottom
Increase-left to right
Which of the following statements concerning the properties of ionic compounds is NOT correct?
A: The properties of ionic compounds are very similar to the properties of the elements they are made from.
B:All nitrates are soluble.
C:The formula unit of an ionic solid gives the smallest whole number ratio of cations to anions in the compound.
D:Ionic compounds conduct electricity when they are molten, but not when they are solid.
A