Answer:
The number of moles of potassium hydroxide, KOH required to make 4 moles of K₂SO₄ is 8 moles of KOH
Explanation:
2KOH + H₂SO₄ → K₂SO₄ + 2H₂O
From the above reaction, we have 2 moles of KOH combining with 1 mole of H₂SO₄ to produce 1 mole of K₂SO₄ and 2 moles of H₂O.
Therefore the number of moles of potassium hydroxide that will be needed to make 4 moles of K₂SO₄ is;
8KOH + 4H₂SO₄ → 4K₂SO₄ + 8H₂O
8 moles of KOH is required to make 4 moles of K₂SO₄.
Answer:
Explanation:
check the attachment for the propose neutral structure for each compound that is consistent with the data.
Answer:
Chemical change
Explanation:
From all indicators, Aurelia is seeing a chemical change occurring in the reaction here.
A chemical change is a change in which new substances are produced. For every chemical change:
- they are not easily reversible
- they lead to production of new kinds of substances
- involves mass change
- require considerable amount of energy.
We start off and end with:
Metal + Acid → Black metal + rising gaseous bubbles
Clearly, it is shown that new products are formed and this reaction is impossible to reverse in order to get the reactants back.
This is a typical chemical change.
The given dehydration equation is,

Cadmiumnitrate tetrahydrate when heated dehydrates releasing the combined water as water vapor. The reaction produces 4 moles of gaseous product water vapor. So, the degree of disorder or randomness increases. Hence, the sign of change in entropy is positive.
This reaction is spontaneous at room temperature even if it is endothermic as the sign of change in entropy is positive.
Answer:
Pb(NO3)2
Cd(NO3)2
Na2SO4
Explanation:
In the first part, addition of HCl leads to the formation of PbCl2 which is poorly soluble in water. This is the first precipitate that is filtered off.
When the pH is adjusted to 1 and H2S is bubbled in, CdS is formed. This is the second precipitate that is filtered off.
After this precipitate has been filtered off and the pH is adjusted to 8, addition of H2S and (NH4)2HPO4 does not lead to the formation of any other precipitate.
The yellow flame colour indicates the presence of Na^+ which must come from the presence of Na2SO4.