ΔHfo stands for <span>standard heat of formation for a compound.
Heat of formation of compound is mathematically expressed as,
</span>∑Hproducts - ∑Hreactants
<span>
If value of </span>ΔHfo is negative, it suggest that is exothermic reaction. If ΔHfo is positive, it suggest that it is endothermic reaction. <span>
</span>
Answer:
Explanation:
Molarity of NaOAc needed
Using the Henderson-Hasselbalch Equation calculate base molarity needed given [HOAc] = 1.00M and pKa(NaOAc) = 4.75 and [HOAc] = 1.00m.
pH = pKa + log [NaOAc]/[HOAc]
5.00 = 4.75 + log[NaOAc]/[1.00M]
5.00 - 4.75 = log [NaOAc] - log[1.00M]
log [NaOAc] = 0.25 => [NaOAc] = 10⁰·²⁵ M = 1.78
Given 10ml of HOAc, how much (ml) 1.78M NaOAc to obtain a buffer pH of 5.00.
Determine Volume of Base Needed
(M·V)acid = (M·V)base => V(base) = (M·V)acid / (M)base
Vol (NaOAc) needed = (1.00M)(0.010L)/(1.78M) = 0.0056 liter = 5.6 ml.
Checking Results:
5.00 = 4.75 + log [1.78M]/[1.00M] = 4.75 + 0.25 = 5.00 QED.
In Bohr's atomic model, an atom consist of a nucleus that is positively charged and is being surrounded by electrons that are said to travel in orbits or circular manner around. It is compared to the solar system where the nucleus is equivalent to the sun and the electrons are the planets.
Given :
a.
b.
c.
d.
.
To Find :
Find the most likely vale of x for each one .
Solution :
a .
Because boron have valency of 3 .
So , x = 3 .
b . 
Valency of carbon is 4 .
x = 4 .
c . 
Valency of nitrogen is 3 .
Therefore , x = 3 .
d . 
Now ,we know valency of carbon is 4 and hydrogen is 1 .
Also , two hydrogen are already there .
So , only 2 electrons left to share .
Since , chlorine have valency of 1 .
Therefore , only 2 electrons of chlorine can connect .
x = 2 .
Hence , this is the required solution .
Because it can be balanced in an infinite number of ways so it would need to be rewritten in a simpler form.