Answer:
∴ Q = -7.52kCal
Explanation:
Using the formula for specific heat capacity:
Q = mcΔT
where ΔT = change in temperature (final - initial) = (0 - 100)°C = -100°C
m = mass (g) = 75g
c = specific heat capacity = 4.2 J/g°C in water
⇒ Q = 75 × 4.2 × -100
= -31,500J
But 1J - 0.000239kCal
<u>∴ Q = -7.52kCal</u>
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Let me know if I can be of further assistance.
Answer:
Since Beryllium has a larger atomic radius than Sulphur its electrons are not strongly attracted to the nucleus hence lost easily. But Sulphur has a small atomic radius hence electrons are more closely attracted to the nucleus.
Answer:
547.5g
Explanation:
To get the mass, you need moles.
moles = (molarity)(Liters)
moles = (1.230M)(4.200L) = 5.166 moles Na2CO3
Now, just use stoichiometry
molar mass of Na2CO3 = 2(mass of Na) + (mass of C) + 3(mass of O)
= 2(22.9) + 12.01 + 3(16) = 105.99g/mol
5.166moles(105.99g/mol)
= 547.544
But, the measurements given had 4 significant figures, so in chemistry we write:
547.5g
The concentration of [H3O⁺]=2.86 x 10⁻⁶ M
<h3>Further explanation</h3>
In general, the weak acid ionization reaction
HA (aq) ---> H⁺ (aq) + A⁻ (aq)
Ka's value
![\large {\boxed {\bold {Ka \: = \: \frac {[H ^ +] [A ^ -]} {[HA]}}}}](https://tex.z-dn.net/?f=%5Clarge%20%7B%5Cboxed%20%7B%5Cbold%20%7BKa%20%5C%3A%20%3D%20%5C%3A%20%5Cfrac%20%7B%5BH%20%5E%20%2B%5D%20%5BA%20%5E%20-%5D%7D%20%7B%5BHA%5D%7D%7D%7D%7D)
Reaction
HC₂H₃O₂ (aq) + H₂O (l) ⇔ (aq) + H₃O⁺ (aq) Ka = 1.8 x 10⁻⁵
![\tt Ka=\dfrac{[C_2H_3O^{2-}[H_3O^+]]}{[HC_2H_3O_2]}}\\\\1.8\times 10^{-5}=\dfrac{0.22\times [H_3O^+]}{0.035}](https://tex.z-dn.net/?f=%5Ctt%20Ka%3D%5Cdfrac%7B%5BC_2H_3O%5E%7B2-%7D%5BH_3O%5E%2B%5D%5D%7D%7B%5BHC_2H_3O_2%5D%7D%7D%5C%5C%5C%5C1.8%5Ctimes%2010%5E%7B-5%7D%3D%5Cdfrac%7B0.22%5Ctimes%20%5BH_3O%5E%2B%5D%7D%7B0.035%7D)
[H₃O⁺]=2.86 x 10⁻⁶ M
Where is the picture to this?
