O or Oxygen because it needs electrons to be stable causing it to be an anion with a 2- charge to have a complete shell while Aluminum would be an cation with a 3+ charge, Potassium or K with a 1+ charge, and Argon wouldn’t be an anion because it is a noble gas and is already stable and don’t need electrons due to a full shell.
Answer: CrO₄⁻ and Ba²⁺
Explanation:
1) Chemical equation given:
2H⁺ + CrO₄⁻ + Ba²⁺ + 2OH⁻ → Ba²⁺ + CrO₄⁻ + 2H₂O
2) Analysis
That is an oxidation-reduction equation (some species are been oxidized and others are being reduced).
The given equation is known as total ionic equation, because it shows all the species as ions that are part of the reaction.
2) Specator ions
Spectator ions are the ions that do not change their oxidation state and are easily identified as they are the same in the reactant and product sides.
Here the ions that are the same in the reactant and product sides are:
CrO₄⁻ and Ba²⁺
3) Addtitional explanation.
Once you identify the spectator ions you can delete them from the equation to obtain the net ionic equation , which in this case turns to be:
2H⁺ + 2OH⁻ → 2H₂O
But this is not part of the question; it is some context to help you understand the use of the spectator ions concept.
Answer:
<h2>118,438.5 moles</h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
We have the final answer as
<h3>118,438.5 moles</h3>
Hope this helps you
<u>Given:</u>
Initial temperature, T1 = 20 C
Final temperature, T2 = 40 C
<u>To determine:</u>
The temperature change
<u>Explanation:</u>
Convert degree C to Kelvin
Temperature in Kelvin = degree C + 273
T1 = 20 + 273 = 293 K
T2 = 40 + 273 = 313 K
Incremental temperature change = T2 - T1 = 313-293 = 20 K
Ans: The temperature change in kelvin is 20 K
Physical change is where u change physically or on the "outside" hope this helps, have a great day!
