Chapter 1: Notes Package Flashcards
How can you count the number of Significant Digits?
Count all the numbers after the number 0s
How do you know how many significant digits you should round to when adding or subtracting?
You round to the least number of decimal places of the numbers used
How do you know what number of significant digits to round to when multiplying and dividing?
Round to the least number of significant digits
When doing a combined number of calculations, how do you know how many significant digits to round to?
Round to the least number of significant digits
Which types of numbers will have an infinite amount of significant digits?
Exact numbers have an infinite number of significant digits but they are generally not reported. ex. 2 pencils
Defined numbers also have an infinite number of significant digits. ex 60s/min
What are the 3 main groups of the periodic table?
Metals, Non-metals, metalloids
What are characteristics of metals?
- Shiny
- Metallic Lustre
- Good conductors of heat and electricity
- Malleable, ductile
- Solid at room temperature, except for mercury
What are characteristics of non-metals?
- Dull
- Does not conduct heat and electricity well
- Brittle
- Solid, liquid and gas at room temperature
What are characteristics of metalloids?
- Border staircase line except for aluminum
- Often brittle solids
- Conduct electricity but not as well as metals
What are characteristics of halogens?
Group 17, extremely reactive with fluorine being the most reactive
What are characterisitcs of Noble gases?
Groups 18, very low chemical reactivity
What is the max number of electrons in each energy level?
Level 1: 2
Level 2: 8
Level 3: 8
Level 4: 18
What does the period of each electron sits in represent?
They represent the number of energy levels an electron has
What are Valence electrons?
Electrons in the outermost shell that is not full
What can valence electrons do?
They are available for covalent bond or electron exchange to form ions
How would you write a Bohr electron diagram?
Write the number of protons and neutrons in the middle, the write dots on each level to represent the number of electron
How do you draw a condensed Bohr diagram?
Start with 0 at the bottom the write the total number of electron above. Each new row you right the electrons needed at each energy level
What is an ion?
An element that has a positive or negative charge. Which means they are gaining or losing electrons
How can you tell if an atom has gained electrons?
Their charge is negative
How can you tell if an atom has lost electrons?
Their charge is positive
Why do atoms gain or lose electrons?
So they have the same number of electrons as the nearest noble gas
What are Cations and how do they form?
They are positively charged ions. They form when metals lose their valence electrons
What are multivalent electrons?
Ions that have more than one stable charge
What are anions?
Ions formed when a non-metal gains electrons into its outer energy level
