The chemical standard used as a basis for the quantity of a mole is the carbon-12. Thus, the answer is letter D. By definition a mole is the number of atoms that would compose 12 g of the carbon-12. The reason for choosing such is that carbon is plentiful and not too hard to make isotropically pure.
Answer:
See Explanation
Explanation:
The equation of the reaction;
KHSO4(aq) + KOH(aq) -------> K2SO4(aq) + H2O(l)
Number of moles of KHSO4 = 49.6 g/136.169 g/mol = 0.36 moles
Since the reaction is in a mole ratio of 1:1, 0.36 moles of K2SO4 is produced.
Number of moles of KOH = 25.3 g/56.1056 g/mol = 0.45 moles
Since the reaction is 1:1, 0.45 moles of K2SO4 is produced
Hence K2SO4 is the limiting reactant.
Mass of K2SO4 formed = 0.36 moles of K2SO4 * 174.26 g/mol = 62.7 g
So;
1 mole of KHSO4 reacts with 1 mole of KOH
0.36 moles of KHSO4 reacts with 0.36 * 1/1 = 0.36 moles of KOH
Amount of excess KOH = 0.45 moles - 0.36 moles = 0.09 moles
Mass of excess KOH = 0.09 moles * 56.1056 g/mol = 5 g of excess KOH
Answer:
Explanation:
Every acid (HA) tends to disolve into proton (
) and anion (
) in aqueous solution. Acid strength can be determined by measuring this tendency to separate into proton an anion. Strength of an acid can be quantified by its acid dissociation value - Ka. A strong acid will have a tendency to easily release proton and will have larger Ka value and smaller logarithmic value (pKa = - logKa) similar to calculating pH of the solution. So the easiest way to resolve this issue is by looking for Ka or pKa value of the acid (This table may be useful in more complex tasks and is attached below). However, stronger acid can be determined elsehow.
a) Carbon is element 14 with 4 valent electrons and sulfur is element 16 with 6 valence electrons. Thus, sulfur has stronger electronegativity (tendency to attract bonded electrons towards itself). This means that sulfur will hold oxygen tighter to itself so the hydrogen bond to it can be more easily separated from it. is more acidic in aqueous solution.
b) In 
, phosphorus holds one double bond with oxygen and three OH group equally. To show an acidic tendency, phosphorus would need to let go one hydrogen out of one of OH groups. In , phosporus holds two double bong with oxygen, one OH and one hydrogen, all single and lonely, ready to leave phosphorus and show acidic characteristics in aqueous solution. Thus, is more acidic compound.
C) In all Cl acids, the electron density is placed around Cl so the more oxygen around Cl, the more acidic will be the chemical. This is comparable to an oxidation state - the bigger oxidation state, the stronger acid will be:
can reasonably be expected to be more acidic in aqueous solution.
It is 50. The answer is 50. 10x5=50 50x1=50
Answer:
3 x 10²⁴ molecules
Explanation:
A mole is just a name that we use to substitute a number, just like a dozen means 12, a mole means 6.022 x 10²³. This gives us the unit conversion of 6.022 x 10²³ molecules SO₂/1 mol SO₂.
Round to the lowest number of significant figures to get 3 x 10²⁴ molecules SO₂
