The correct option is 2.
For a chemical equation to be balanced, the number of atoms of each element present in the reactants must be the same with that present in the products. If the number of atom of any element at any of the two side of the reaction is not the same, then the equation is not balanced. Looking at the options given above, it will be noticed that for option 2, the number of Sr atom at the reactant side is 1 while at the product side it is 2. This shows that the equation is not balanced.
NH₄Cl (s) ⇔ NH₃ (g) + HCl (g)
Δn = 2 (gas only)
R = 0.082
T = 427 + 273 = 700 K
4.8 = Kc (0.082 x 700)²
Kc = 1.45 x 10⁻³
1. 12.992 L
2. 2.42 moles
3. 275.52 L
4. 567.844 g
<h3>Further explanation</h3>
Given
moles and volume at STP
Required
mass, volume and moles
Solution
Conditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure). At STP, Vm is 22.4 liters / mol.
1. 0.58 moles ammonia :
Volume = 0.58 moles x 22.4 L = 12.992 L
2. 77.5 grams of O₂ :
Moles = 77.5 grams x (1 mol/32 grams) = 2.42
3. 12.3 mole of Bromine gas :
Volume = 12.3 mole x (22.4 L/1 mole) = 275.52 L
4. 4.8 moles iron(II)chloride :
Mass = 4.48 moles x molar mass ( 126,751 g/mol) = 567.844 g
A lunar eclipse can be photographed sometimes when Earth is in between the sun and the Moon.
<h3>Why lunar eclipse occur?</h3>
A lunar eclipse occurs when the Sun, Earth, and Moon align in the same line in which the Moon passes into Earth's shadow. In a total lunar eclipse, the entire Moon falls within the darkest part of Earth's shadow, called the umbra so we can conclude that claim 2 is the right answer about lunar eclipse.
Learn more about eclipse here: brainly.com/question/1077760
Answer: The pH of 0.10 M 
is 4.49.
Explanation:
Given: Initial concentration of 
= 0.10 M
Let us assume that amount of dissociates is x. So, ICE table for dissociation of is as follows.
![Cu(H_{2}O)^{2+}_{6} \rightleftharpoons [Cu(H_{2}O)_{5}(OH)]^{+} + H_{3}O^{+}](https://tex.z-dn.net/?f=Cu%28H_%7B2%7DO%29%5E%7B2%2B%7D_%7B6%7D%20%5Crightleftharpoons%20%5BCu%28H_%7B2%7DO%29_%7B5%7D%28OH%29%5D%5E%7B%2B%7D%20%2B%20H_%7B3%7DO%5E%7B%2B%7D)
Initial: 0.10 M 0 0
Change: -x +x +x
Equilibrium: (0.10 - x) M x x
As the value of 
is very small. So, it is assumed that the compound will dissociate very less. Hence, x << 0.10 M.
And, (0.10 - x) will be approximately equal to 0.10 M.
The expression for value is as follows.
![K_{a} = \frac{[Cu(H_{2}O)^{2+}_{6}][H_{3}O^{+}]}{[Cu(H_{2}O)^{2+}_{6}]}\\1.0 \times 10^{-8} = \frac{x \times x}{0.10}\\x = 3.2 \times 10^{-5}](https://tex.z-dn.net/?f=K_%7Ba%7D%20%3D%20%5Cfrac%7B%5BCu%28H_%7B2%7DO%29%5E%7B2%2B%7D_%7B6%7D%5D%5BH_%7B3%7DO%5E%7B%2B%7D%5D%7D%7B%5BCu%28H_%7B2%7DO%29%5E%7B2%2B%7D_%7B6%7D%5D%7D%5C%5C1.0%20%5Ctimes%2010%5E%7B-8%7D%20%3D%20%5Cfrac%7Bx%20%5Ctimes%20x%7D%7B0.10%7D%5C%5Cx%20%3D%203.2%20%5Ctimes%2010%5E%7B-5%7D)
Hence, ![[H_{3}O^{+}] = 3.2 \times 10^{-5}](https://tex.z-dn.net/?f=%5BH_%7B3%7DO%5E%7B%2B%7D%5D%20%3D%203.2%20%5Ctimes%2010%5E%7B-5%7D)
Formula to calculate pH is as follows.
![pH = -log [H^{+}]](https://tex.z-dn.net/?f=pH%20%3D%20-log%20%5BH%5E%7B%2B%7D%5D)
Substitute the values into above formula as follows.
![pH = -log [H^{+}]\\= - log (3.2 \times 10^{-5})\\= 4.49](https://tex.z-dn.net/?f=pH%20%3D%20-log%20%5BH%5E%7B%2B%7D%5D%5C%5C%3D%20-%20log%20%283.2%20%5Ctimes%2010%5E%7B-5%7D%29%5C%5C%3D%204.49)
Thus, we can conclude that the pH of 0.10 M is 4.49.
