Answer:
B. Lower
Explanation:
Remember that the pH is calculated as
-log (H30 +)
That is, at a higher concentration of H30 +, with the -log, the pH value decreases and vice versa.
With a concentration 1e-5, it yields a pH of 5.00 and with 1e-2 a value of 2.00
Answer:
Base
Explanation:
Why is Alka-Seltzer a base?
Alka-Seltzer contains sodium bicarbonate and citric acid. The sodium citrate acts as an antacid. Excess sodium bicarbonate from the Alka-Seltzer acts to neutralize base.
Answer:
The reaction combines the sodium with the hydrogen and oxygen in water to form sodium hydroxide and hydrogen gas, and you get a lot of energy released as heat as well. This heat actually melts any remaining sodium that has not reacted yet, and ignites the hydrogen gas, so you get the bang and the flash.
Explanation:
ΔHrxn = ΣδΗ(bond breaking) - ΣδΗ(bond making)
Bond enthalpies,
N ≡ N ⇒ 945 kJ mol⁻¹
N - Cl ⇒ 192 kJ mol⁻¹
Cl - Cl⇒ 242 kJ mol⁻¹
According to the balanced equation,
ΣδΗ(bond breaking) = N ≡ N x 1 + Cl - Cl x 3
= 945 + 3(242)
= 1671 kJ mol⁻¹
ΣδΗ(bond making) = N - Cl x 3 x 2
= 192 x 6
= 1152 kJ mol⁻¹
δHrxn = ΣδΗ(bond breaking) - ΣδΗ(bond making)
= 1671 kJ mol⁻¹ - 1152 kJ mol⁻¹
= 519 kJ mol⁻¹
