Answer:
Na ·
Explanation:
Hello!
In this case, since the Lewis dot structure of any element illustrates the number of valence electrons at the outer shell; we can set up the electron configuration of sodium to obtain:
We can see there is only one valence electron, for that reason the Lewis dot structure is:
Na ·
Whereas the dot represents the valence electron.
Best regards!
In my opinion the answer is D
Answer:
This is the balanced equation:
Pb(NO₃)₂ (aq) + 2NaI (aq) → 2NaNO₃ (aq) + PbI₂ (s) ↓
Explanation:
This are the reactants:
PbNO₃
NaI
Iodide can react to Pb²⁺ to make a solid compound.
Answer:
43.05 moles of Al needed to react with 28.7 moles of FeO.
Explanation:
Given data:
Moles of FeO = 28.7 mol
Moles of Al needed to react with FeO = ?
Solution:
Chemical equation:
2Al + 3FeO → 3Fe + Al₂O₃
Now we will compare the moles of Al with FeO.
FeO : Al
2 : 3
28.7 : 3/2×28.7 = 43.05 mol
Thus 43.05 moles of Al needed to react with 28.7 moles of FeO.
We can calculate how long the decay by using the half-life equation. It is expressed as:
A = Ao e^-kt
<span>where A is the amount left at t years, Ao is the initial concentration, and k is a constant.
</span><span>From the half-life data, we can calculate for k.
</span>
1/2(Ao) = Ao e^-k(30)
<span>k = 0.023
</span>
0.04Ao = Ao e^0.023(t)
<span>t = 140 sec</span>
