Unit 4 Quantitative Chemistry Flashcards
Sate the law of conservation of mass
No atoms are lost or gained so the mass of the reactants equals the mass of the products
What are the reactants
The starting materials
What are the products
The chemicals formed in a reaction
How are ionic compounds formed
When a metal reacts with a non metal
What ions do
a) metals form
b) non-metals form
A) positive
B) negative
What ions do group two produce
2+ ions
What ions do group seven form
-1
What elements do not follow the pattern of group number is the ion number
Transition metals
What non metal ions form a positive charge
H+ ions - Hydrogen
NH4 + ions - ammonium
What’s the key rule when determines the ionic compound formula
The charges of the compound must cancel out like Na+OH-
What is the relative atomic mass
It is the average mass of the isotopes of the element taking account their abundance
What’s relative formula mass
It’s the sum of the atomic masses in the formula
How do we work out the relative atomic mass
Sum of The mass numbers multiplied each ones abundance
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100
Do we take into consideration the big numbers when working out relative formula mass
Noooooo
What’s the relative formula mass of
A) CH4
B) 2CH4
A) 16
B) 16
How do you work out the percentage by mass
Relative atomic mass of the element * how many atoms they are
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Relative formula mass
