Answer:
1st step : find the number of moles for the known substance
number of moles =mass/ relative molecular mass
n=23/Li2O2
n=23/(14+32)
n =23/46
n= 0,5moles
2nd step : balance the equation
2Li202 +2H20-----> 4LiOH +O2
3rd step : find the mole ratio of the known or stated using the balanced equation
Li2O2 : O2
2 : 1
4th step :find the number of moles for the asked using the mole ratio using simple proportion
Li2O2 :O2
2 :1
0,5 :???
0,5/2 ×1
= 0,25moles for (O2)
5th step : find the asked either mass , volume , concentration
number of moles = volume/molar gas volume
volume = number of moles × molar gas volume
v = 0,25moles × 28dm^3
v= 7 dm^3 of (O2)
Answer:
A
Explanation:
Mass is a raw measurement, weight is effected by gravity
Valence electrons are located on the outermost energy level and determine how reactive an atom will be
Mole<span>: the amount of a substance that contains 6.02 x </span>10<span>. 23 respective particles of that substance. Avogadro's number: 6.02 x </span>10<span>. 23. Molar Mass: the mass of one </span>mole<span> of an element. CONVERSION FACTORS: 1 </span>mole<span> = 6.02 x </span>10<span>. 23 </span>atoms<span> 1 </span>mole<span> = </span>atomic<span> mass (g). Try: 1. How </span>many atoms<span> are in 6.5</span>moles<span> of zinc</span>
I think the answer is 1s²2s²2p⁶. Since neon has an atomic number of 10, we know that it needs to have 10 electrons and since it is in the second row it cannot have any d electrons which makes the first option incorrect. The second option is incorrect because the 2s⁴ can't exist since s orbitals can only hold 2 electrons. The fourth option cannot be right because it again neon cannot have d electrons due to it being in the second row.
I hope this helps. Let me know if anything is unclear.