Answer:
We need 226 grams of FeS
Explanation:
Step 1: Data given
Mass of FeCl2 = 326 grams
Molar mass FeCl2 = 126.75 g/mol
Step 2: The balanced equation
FeS + 2 HCl → H2S + FeCl2
Step 3: Calculate moles FeCl2
Moles FeCl2 = 326 grams / 126.75 grams
Moles FeCl2 = 2.57 moles
Step 4: Calculate moles FeS needed
For 1 mol H2S and 1 mol FeCl2 produced, we need 1 mol FeS and 2 moles HCl
For 2.57 moles FeCl2 we need 2.57 moles FeS
Step 5: Calculate mass FeS
Mass FeS = 2.57 moles * 87.92 g/mol
Mass FeS = 226 grams FeS
We need 226 grams of FeS
Answer:The ideal gas law is represented mathematically as: PV=nRT. P- pressure, V- volume, n-number of moles of gas, R- ideal gas constant, T- temperature.
Explanation:The ideal gas law is used as a prediction of the behavior of many gases, when subjected to different conditions.
he ideal gas law has so many limitations.
An increase in the pressure or volume, decreases the number of moles and temperature of the gas.
Empirical laws that led to generation of the ideal gas laws, considered two variables and keeping the others constant. This empirical laws include, Boyle's law, Charles's law, Gay Lusaac's law and Avogadro's law.
"Silver chloride is essentially insoluble in water" this statement is true for the equilibrium constant for the dissolution of silver chloride.
Option: b
<u>Explanation</u>:
As silver chloride is essentially insoluble in water but also show sparing solubility, its reason is explained through Fajan's rule. Therefore when AgCl added in water, equilibrium take place between undissolved and dissolved ions. While solubility product constant
for silver chloride is determined by equilibrium concentrations of dissolved ions. But solubility may vary also at different temperatures. Complete solubility is possible in ammonia solution as it form stable complex as water is not good ligand for Ag+.
To calculate
firstly molarity of ions are needed to be found with formula: 
Then at equilibrium cations and anions concentration is considered same hence:
![\left[\mathbf{A} \mathbf{g}^{+}\right]=[\mathbf{C} \mathbf{I}]=\text { molarity of ions }](https://tex.z-dn.net/?f=%5Cleft%5B%5Cmathbf%7BA%7D%20%5Cmathbf%7Bg%7D%5E%7B%2B%7D%5Cright%5D%3D%5B%5Cmathbf%7BC%7D%20%5Cmathbf%7BI%7D%5D%3D%5Ctext%20%7B%20molarity%20of%20ions%20%7D)
Hence from above data
can be calculated by:
= ![\left[\mathbf{A} \mathbf{g}^{+}\right] \cdot[\mathbf{C} \mathbf{I}]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cmathbf%7BA%7D%20%5Cmathbf%7Bg%7D%5E%7B%2B%7D%5Cright%5D%20%5Ccdot%5B%5Cmathbf%7BC%7D%20%5Cmathbf%7BI%7D%5D)
C) and d) are physical changes while b) is chemical
Answer:
(a) 
(b) 
(c) 
(d) 
(e) 
Explanation:
To calculate de pH of an acid solution the formula is:
![pH = -Log ([H^{+}]) = 1](https://tex.z-dn.net/?f=pH%20%3D%20-Log%20%28%5BH%5E%7B%2B%7D%5D%29%20%3D%201)
were [H^{+}] is the concentration of protons of the solution. Therefore it is necessary to know the concentration of the protons for every solution in order to solve the problem.
(a) and (c) are strong acids so they dissociate completely in aqueous solution. Thus, the concentration of the acid is the same as the protons.
(b) and (e) are strong bases so they dissociate completely in aqueous solution too. Thus, the concentration of the base is the same as the oxydriles. But in this case it is necessary to consider the water autoionization to calculate the protons concentration:
![K_{w} =[H^{+} ][OH^{-}]=10^{-14}](https://tex.z-dn.net/?f=K_%7Bw%7D%20%3D%5BH%5E%7B%2B%7D%20%5D%5BOH%5E%7B-%7D%5D%3D10%5E%7B-14%7D)
clearing the ![[H^{+} ]](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%20%5D)
![[H^{+} ]=\frac{10^{-14}}{[OH^{-}]}](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%20%5D%3D%5Cfrac%7B10%5E%7B-14%7D%7D%7B%5BOH%5E%7B-%7D%5D%7D)
(d) is a weak base so it is necessary to solve the equilibrium first, knowing 
The reaction is
→
so the equilibrium is

clearing the <em>x</em>

![x=[H^{+}]=4.93x10^{-10}](https://tex.z-dn.net/?f=x%3D%5BH%5E%7B%2B%7D%5D%3D4.93x10%5E%7B-10%7D)