Answer:
d. N
Explanation:
Chemical equation:
Pb(NO₃)₂(aq) + K₂SO₄(aq) → PbSO₄(s) + KNO₃(aq)
Balanced Chemical equation:
Pb(NO₃)₂(aq) + K₂SO₄(aq) → PbSO₄(s) + 2KNO₃(aq)
Ionic equation:
Pb²⁺(aq) + 2NO₃⁻(aq) + 2K⁺(aq) + SO₄²⁻(aq) → PbSO₄(s) + 2K⁺(aq) + 2NO₃⁻(aq)
Net ionic equation:
Pb²⁺(aq) + SO₄²⁻(aq) → PbSO₄(s)
The NO₃⁻(aq) and K⁺(aq)are spectator ions that's why these are not written in net ionic equation. The PbSO₄ can not be splitted into ions because it is present in solid form.
Spectator ions:
These ions are same in both side of chemical reaction. These ions are cancel out. Their presence can not effect the equilibrium of reaction that's why these ions are omitted in net ionic equation.
Answer:
moles of ammonia produced = 0.28 moles
Explanation:
The reaction is

As per equation, one mole of nitrogen will react with three moles of hydrogen to give two moles of ammonia
So 0.140 moles of nitrogen will react with = 3 X 0.140 moles of Hydrogen
= 0.42 moles of hydrogen molecule.
this will give 2 X 0.140 moles of ammonia = 0.28 moles of ammonia
the moles of ammonia produced = 0.28 moles
Here the nitrogen is limiting reagent.
Answer:
Explanation:
Sn(WC)2
if it is tungsten carbide this should be correct but there are many versions of carbide
Sn(MC2)2
could also be possible
the 2 next to MC should be a subscript
If it has a metal and a nonmetal. Not sure if this helps, but I hope it does :)
Answer:
D
Explanation:
There are principally three states of matter. These are the solid, liquid and gaseous states. The gaseous state has the highest degree of disorderliness as gas particles can move randomly while the solid state has the highest level of compactness.
Hence, we need to be adequately fed with information as regards the phase change to know if entropy has decreased or increased.
A. is wrong
Evaporation is a change of state to the gaseous state meaning there is an increased entropy.
B. is wrong
Sublimation is a change of state which means a solid substance like iodine or naphthalene changes its state directly to the gaseous state. There is an increased entropy here too.
C is wrong
Melting of ice means going from ice block to liquid water. This is synonymous to going from the solid state to the liquid state which is an increased entropy
D is correct
Condensation involves going from the gaseous state to the liquid state. This means going from a less ordered state to a more ordered state. This is accompanied by an entropy decrease.
E is wrong
While there are some processes that increase entropy, we also have some process that decrease entropy.