Answer:
Helium atom
Explanation:
For the RTGs flown by the United States, the radioisotope has been some chemical form of plutonium-238 (238Pu or Pu-238). Plutonium-238 decays primarily by the emission of an alpha particle (a helium atom without its electrons).
Answer:
All of the above readings are used to determine the availability of minerals.
A mineral is a naturally occurring substance, representable by a chemical formula, that is usually solid and inorganic, and has a crystal structure. It is different from a rock, which can be an aggregate of minerals or non-minerals and does not have a specific chemical composition.
The correct answer between all the choices given is the last choice or letter D. I am hoping that this answer has satisfied your query and it will be able to help you in your endeavor, and if you would like, feel free to ask another question.
First, we need to get moles of HA =molarity * volume
= 0.1 m * 0.075 L = 0.0075 moles
moles of NaOH = molarity * volume
= 0.1 * 0.03 L = 0.003 moles
from the reaction equation:
HA(aq) + NaOH(aq) → NaA(aq) + H2O(l)
that means the final moles' HA = 0.0075 - 0.003 =0.0045 moles
when the total volume is = 0.075 + 0.03 L = 0.105 L
∴ [HA] = moles / volume
= 0.0045 / 0.105 L = 0.043 m
[A^-] = 0.003 / 0.105 L = 0.029 m
then by using H-H equation:
PH = Pka + ㏒[A^-] / [HA]
by substitution, we can get Pka:
5.5 = Pka+ ㏒ (0.029 /0.043)
∴ Pka = 5.67
when Pka = - ㏒Ka
5.67 = -㏒ Ka
∴Ka = 2 x 10^-6
Answer:
Explanation:
Q1. Mass of Cu
(a) Write the equation for the half-reaction.
Cu²⁺ + 2e⁻ ⟶ Cu
The number of electrons transferred (z) is 2 mol per mole of Cu.
(b) Calculate the number of coulombs
q = It
(c) Mass of Cu
We can summarize Faraday's laws of electrolysis as
Note: The answer can have only two significant figures because that is all you gave for the time.
Q2. Current used
(a) Write the equation for the half-reaction.
Ag⁺ + e⁻ ⟶ Ag
The number of electrons transferred (z) is 1 mol per mole of Ag.
(a) Calculate q
(b) Calculate the current
t = 3 h = 3 × 3600 s = 10 800 s
Note: The answer can have only one significant figure because that is all you gave for the time.