Atomic Structure and Isotopes Flashcards
What is an isotope?
An atom with the same number of protons (of the same element) but a different number of neutrons
What is the formula of a sulfate?
SO4
What is the formula of a nitrate?
(NO3)
What is the formula of a hydroxide?
(OH)
Give the definition of relative atomic mass
The weighted mean mass of an atom of an element relative to 1/12th of the mass of an atom of carbon 12
Give the definition of the relative isotopic mass
The mass of an isotope relative to 1/12 of the mass of an atom of carbon 12
What is avogadros constant?
6.02 x 1023
How do you calculate the numbers that will be in the empirical formula
- You find the moles of each of the atoms in the element
- Divide each of the moles by the smallest moles
- That will give you the ratio
- Use this to write the empirical formula
The little numbers in the empirical formula of a compound must always be [blank]
fill in the blank
The little numbers in the empirical formula of a compound must aways be whole numbers
!!! so if you get a decimal number ending in .5 DOUBLE EVERYTHING, and if its a decimal that can easily be rounded ROUND IT NOWWWWW
Which type of structure is written using empirical formula?
GIANT STRUCTURES (Covalent AND Ionic)
Which type of structure is written using molecular formula?
Simple/small covalent bonds
How do you calculate the molecular formula?
- Calculate the empirical formula of the compound
- Calculate the Mr of the compound using this empirical formula
- Divide the given relative molecular molar mass by the Mr (molar mass) of the empirical formula
- Multiply the quotient by the Mr of the empirical formula
- Et voila! you have your molecular formular
How do you use the empirical formula to calculate the molecuar formula?
- You divide the given relative molecular Mr by the Mr of the compound which is found using the empirical formula
- Then multiply each subscript in the empirical formula by this quotient to find the molecular formula
What is Avogadro’s LAW
not constant but his LAW
In room temperature and pressure, one mole of gas occupies 24 dm3
In what conditions does Avogadro’s LAW not work
When it is not room temperature and pressure
What is the equation for Avogadro’s Law?
moles of GAS= volume/24dm3
or
volume= moles of GAS x 24dm3
or 24000cm3 bc that equals 24dm3
What is the equation for ideal gas
pV=nRT
What does p stand for in the ideal gas equation?
Pressure
What are the units of pressure in the ideal gas equation?
Pa, Pascals
How many Pascals in 1 Atmosphere?
101325 Pascals
How many atmospheres in 101325 Pascals?
1 Atmosphere
What does the V stand for in the ideal gas equation?
Volume