Boiling Point and Freezing Point., Surface Tension, Heat of Vaporization, and Vapor Pressure, Viscosity and Cohesion, solid State, Liquid State, Gas State.
Answer:
See Explanation
Explanation:
1) Let us recall that;
Mass number = number of protons + number of neutrons
Where;
Number of protons = ?
Number of neutrons =20
Mass number =39
Number of protons = mass number - number of neutrons
Mass of protons =39 - 20= 19 protons
2) Atomic number = 13
Number of neutrons =14
Then the mass number =13 +14 =27
The symbol of the element is 27X13
The number of protons= the number of electrons =13
The atomic number is the same as the proton number =13
Remember that HCl is a strong acid will dissociate almost 100%
HCl + H₂O --> H₃O⁺ + Cl⁻
pH = -log[H₃O⁺]
pH = -log(0.045) = 1.35
(The rules for sig figs are that if you take the log of a number with x significant figures, then the result should have x significant decimal places.)
The pH is 1.35
<span> Helium only has 2 neutrons
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The answer is A for that question