Answer:
Chloro-Flouro-Carbon
Explanation:
Chloro-Flouro-Carbon (CFC Gas) is used as a refrigerant in fridges and freezers.
Explanation:
Uranium have an unstable nuclei , hence it is a radioactive element , and radioactive element can undergo radioactive decay like the alpha decay , beta decay .
Radioactive decay is a spontaneous breakdown of the atomic nucleus which , results in the release of energy along with radioactive particles , like alpha , beta , gamma etc .
Hence ,
The mass is lost from a sample of uranium .
Charge # = protons - electons
Mass # = protons + neutrons
so that would be
3-3= charge#
3+4= mass#
The electron configuration for a atom whose element has a atomic number of 8 (Oxygen) is 2,6
Answer:
b) 3.10
Explanation:
HF ⇄ H
+ + F
Using Henderson-Hasselbalch Equation:
pH = pKa + log [A-]/[HA].
Where;
pKa = Dissociation constant = -log Ka
Hence, pKa of HF = -log 7.2 x 10^-4 = 3.14266
[A-] = concentration of conjugate base after dissociation = moles of base/total volume
= 0.15 x 0.3/0.8
= 0.05625 M
[HA] = concentration of the acid = moles of acid/total volume
= 0.10 x 0.5/0.8
= 0.0625 M
Note: <em>Total volume = 500 + 300 = 800 mL = 0.8 dm3</em>
pH = 3.14266 + log [0.05625/0.0625]
= 3.14267 + (-0.04575749056)
= 3.09691250944
<em>From all the available options below:</em>
<em>a) 2.97
</em>
<em>b) 3.10
</em>
<em>c) 3.19
</em>
<em>d) 3.22
</em>
<em>e) 3.32</em>
The correct option is b.
