Explanation:
The oxidation number of Ni is +4
Answer:
8 electrons
Explanation:
Magnesium is present on group 2.
It has 2 valence electrons.
Electronic configuration of magnesium:
Mg₁₂ = 1s² 2s² 2p⁶ 3s²
1st energy level contain 2 electrons.(1s²)
2nd energy level contain 8 electrons. (2s² 2p⁶)
3rd energy level contain 2 electrons. (3s²)
3rs energy level of magnesium is called valence shell. It contain two valance electrons. Magnesium can easily donate its two valance electrons and get stable electronic configuration.
It react with halogens and form salt. For example,
Mg + Cl₂ → MgCl₂
Answer:
2023.04 g
Explanation:
Magnetite reacts with hydrogen to produce Iron metal and steam. Steam instead of water is produced as the reaction occurs at temperatures above the boiling point of water.
Fe₃O₄ + 4 H₂ → 3 Fe +4 H₂O
From the equation, 1 mole of Fe₃O₄ reacts with 4 moles of H₂.
69.76 grams of H₂ has the following number of moles.
Number of moles= mass/RAM
=69.76/2
=34.88 moles.
The reaction ratio of Fe₃O₄ to H₂ is 1:4
Thus number of moles of magnetite= (1×34.88)/4
=8.72 moles.
Mass= moles × molecular weight
=8.72 moles × (56×3+16×4)
=2023.04 grams
The question is incomplete, here is the complete question:
At elevated temperature, nitrogen dioxide decomposes to nitrogen oxide and oxygen gas
The reaction is second order for 
with a rate constant of 
at 300°C. If the initial [NO₂] is 0.260 M, it will take ________ s for the concentration to drop to 0.150 M
a) 1.01 b) 5.19 c) 0.299 d) 0.0880 e) 3.34
<u>Answer:</u> The time taken is 5.19 seconds
<u>Explanation:</u>
The integrated rate law equation for second order reaction follows:
![k=\frac{1}{t}\left (\frac{1}{[A]}-\frac{1}{[A]_o}\right)](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B1%7D%7Bt%7D%5Cleft%20%28%5Cfrac%7B1%7D%7B%5BA%5D%7D-%5Cfrac%7B1%7D%7B%5BA%5D_o%7D%5Cright%29)
where,
k = rate constant =
t = time taken = ?
[A] = concentration of substance after time 't' = 0.150 M
![[A]_o](https://tex.z-dn.net/?f=%5BA%5D_o)
= Initial concentration = 0.260 M
Putting values in above equation, we get:
Hence, the time taken is 5.19 seconds
