Answer:
d) PO4^3-, HPO4^2-
Explanation:
Basically, an acid and a base which differs only by the presence or absence of proton (hydrogen ion) are called a conjugate acid-base pair.
a) HI, I
This is incorrect. For the acid, HI the conjugate base is I⁻ ion.
b) HCHO2, SO4^2-
This is incorrect, there's no relationship between both entities.
c) CO3^2-, HCI
This is incorrect, there's no relationship between both entities.
d) PO4^3-, HPO4^2-
This is correct. The difference between both entities is the Hydrogen ion. This is the conjugate acid-base pair
Answer:
23.2 g of Al will be left over when the reaction is complete
Explanation:
2Al + 3S → Al₂S₃
1 mol of Al = 26.98 g
1 mol of S = 32.06 g
Mole = Mass / Molar mass
63.8 g/ 26.98 g/m = 2.36 mole of Al
72.3 g / 32.06 g/m = 2.25 mole of S
2 mole of Aluminun react with 3 mole of sulfur
2.36 mole of Al react with (2.36 .3)/2 = 3.54 m of S
As I have 2.25 mole of S, and I need 3.54 S, is my limiting reagent so the limiting in excess is the Al.
3 mole of S react with 2 mole of Al
2.25 mole of S react with (2.25 m . 2)/3 = 1.50 mole
I need 1.50 mole of Al and I have 2.36, that's why the Al is in excess.
2.36 mole of Al - 1.50 mole of Al = 0.86 mole
This is the quantity of Al without reaction.
Molar mass . mole = Mass → 26.98 g/m . 0.86 m = 23.2 g
the answer equals to 29000
The chemical reaction is expressed as:
2H2 + O2 = 2H2O
To determine the amount of oxygen used in the reaction, we use the amount of water produced and the relation of the substances in the reaction we do as follows:
209 g H2O ( 1 mol / 18.02 g ) ( 1 mol O2 / 2 mol H2O ) ( 32 g / 1 mol ) = 185.57 g O2