Answer:
Explanation:
The algebraic sum of all the oxidation numbers of all atoms in a neutral compound is zero.
In order to know the formula of the negative Sulfur ion in pyrite, we must determine its oxidation state.
Let us make the make the oxidation number of sulfur = x
Therefore, FeS₂:
+2 +2x = 0
+2 = -2x
x = -1
The formula of the negative ion is S⁻
HNO3 + Ca —-> H2O + N20 + Ca(NO3)2
Density = mass/volume
Density =12.5/16=0.78125 g/cm^3
Answer: 1. 
increases.
Explanation:
Any change in the equilibrium is studied on the basis of Le-Chatelier's principle.This principle states that if there is any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.
For the given equation:
If the concentration of 
is increased , according to the Le-Chatlier's principle, the reaction has to shift to right or forward direction. In order to do that the concentration of products has to increase.
Thus the concentration of increases.
