Counting Atoms In Compounds
How many TOTAL atoms H₂SO₄
7
How many TOTAL atoms Mg(C₂H₃O₂)₂
15
A compound with parenthesis. Pb(NO3)2, means you _________ number outside the parenthesis times the subscript ________ the parenthesis.
multiply, inside
A __________________ in chemistry is used to tell the reader how many of that element there are in a certain compound.
subscript
The 2 after the parenthesis indicates there are ______ sets of the element combination in the parenthesis. Pb(NO3)(NO3)
two
Number of K in KNO₃
1
NaCl If there is not a subscript listed, it is understood to be ____.
1(one)
HCl Hydrogen = ____ Chlorine = ____
1, 1
NaCl There is ____ atom of Sodium There is _____ atom of Chlorine
1, 1
NaHCO3 Sodium = ____ Hydrogen = ____ Carbon = ____ Oxygen= ____
1, 1, 1, 3
Practice! Mg(OH)2 Magnesium - 1 Oxygen - 2 Hydrogen - 2
1, 2, 2
Pb(NO3)2, In Counting the atoms, you would have the following: Lead - ___ Oxygen - ___ Nitrogen -___
1, 6, 2
Number of O in Al₂(SO₄)₄
16
2H2SO4 This means there are _____ compounds of Sulfuric Acid. H2SO4 H2SO4
2
Number of Al in Al₂(SO₄)₄
2
How many TOTAL atoms Al₂(SO₄)₄
22
How many TOTAL atoms H₂O
3
Number of O in KNO₃
3
Practice! (NH4)3PO4 Nitrogen = ____ Hydrogen = ____ Phosphorus = ____ Oxygen = 4
3, 12, 1,
Number of S in Al₂(SO₄)₄
4
Practice! 2H2O = Hydrogen = _____ Oxygen = _____
4, 2
2H2SO4 Counting the atoms: Hydrogen = ____ Sulfur = ____ Oxygen = ____
4, 2, 8
How many TOTAL atoms Ba(OH)₂
5
Practice! 3H3PO4 = Hydrogen = _____ Phosphorus = _____ Oxygen = _____
9, 3, 12
Each new element is identified by a capital letter Example: H2SO4
Hydrogen, Sulfur, Oxygen
2H2SO4 The ____________ represent the number of molecules that take part in the chemical reaction.
coefficients