maybe 1+8 (4+548) 4/6 4+4
Answer:
moles SO42- = 0.0500 L x 0.20 M=0.010
moles Ba2+ = 0.0500 L x 0.10 M = 0.0050
Ba2+ + SO42- = BaSO4 (s)
moles SO42- in excess = 0.010 - 0.0050=0.0050
total volume = 100 mL = 0.100 L
[SO42-]= 0.0050/0.100= 0.050 M
[Na2SO4] = 2 /2 = 1 M
moles Na2SO4 = 2 M x 0.500 L = 0.500
mass Na2SO4 = 0.500 x 142 g/mol=71.0 g
moles MgBr2 = 46 /184 =0.25
moles Br- = 0.25 x 2 = 0.50
[Br-]= 0.50 / 0.50 L = 1 M
Answer:
* The empirical formula of a compound shows the ratio of elements present in a compound
* The molecular formula of a compound shows how many atoms of each element are present in a molecule of a compound.
Example: the compound butene has a molecular formula of C4H8. The empirical formula
of butene is CH2 because there is a 1:2 ratio of carbon atoms to hydrogen atoms.
Answer is: the third reaction.
Elements in this chemical reaction do not change their oxidation number. Hydrogen has oxydation number +1, sulfur oxidation number is +6, oxygen has oxidation number -2 and barium has +2 on both sides of chemical reaction. In other reactions elements change their oxidation numbers.
