Polylactic acid is the correct answer
Answer:
H₃PO₄ is an acid because donates the proton to fenolate.
Fenolate is the base because accepts the proton from the acid.
Explanation:
Bronsted theory mentioned that acid is the one that donates a proton to another compound and base is the one that receives it.
H₃PO₄ + C₆H₅O⁻ ⇄ H₂PO₄⁻ + C₆H₅OH
acid base conj. base conj. acid
H₃PO₄ is an acid because donates the proton to fenolate.
Fenolate is the base because accepts the proton from the acid.
If we follow the dissociation, the diacid phosphate can donate two more protons, it is still a Bronsted acid, but it can act as an acid or a base. This is called amphoteric.
Answer:
3.75 g.
Explanation:
<em>mass percent is the ratio of the mass of the solute to the mass of the solution multiplied by 100.</em>
<em />
<em>mass % = (mass of solute/mass of solution) x 100.</em>
<em></em>
mass of calcium nitrite = ??? g,
mass of the solution = 25.0 g.
∴ mass % = (mass of solute/mass of solution) x 100
<em></em>
<em>∴ mass of solute (calcium nitrite) = (mass %)(mass of solution)/100</em> = (15.0 %)(25.0 g)/100 = <em>3.75 g.</em>
We can use two equations for this problem.<span>
t1/2 = ln
2 / λ = 0.693 / λ
Where t1/2 is the half-life of the element and λ is
decay constant.
20 days = 0.693 / λ
λ = 0.693 / 20 days
(1)
Nt = Nο eΛ(-λt) (2)
Where Nt is atoms at t time, No is the initial amount of substance, λ is decay constant and t is the time
taken.
t = 40 days</span>
<span>No = 200 g
From (1) and (2),
Nt = 200 g eΛ(-(0.693 / 20 days) 40 days)
<span>Nt = 50.01 g</span></span><span>
</span>Hence, 50.01 grams of isotope will remain after 40 days.
<span>
</span>
<span>Energy = Mass * heat capacity * temperature change so,
</span>The energy added is 435 J and the temperature has to increase since the energy is added.
<span>435 J = 10.0 g * 0.89 J/gC * temperature change </span>
<span>Temperature change = 48.9 C </span>
<span>The initial temperature is 25.0 C, the final temperature is 25.0 C + 48.9 C = 73.9 C.</span>