True but no one know Exactly how many stars there are
Answer:
The question asks for moles, which can be obtained from P-V-T data using the ideal gas
equation: n =
RT
PV .
Now use the rearranged gas law to determine the number of moles in the sample:
!
n = PV
RT = (6.47 x 105 Pa)(5.65 x 10-4m3
)
(8.314 J
mol K )(21.7 + 273.15 K) = 0.149 mol.
All conditions except the pressure and volume are fixed, so P1V1 = P2V2 can be used: 3.62 L
101kPa
(647 kPa)(0.565 L)
2
1 1
2 = =
P
PV V
Explanation:
Answer:
Work is a force causing the movement or displacement of an object
law of conservation mass:
1. Atoms cannot be created or destroyed in a chemical reaction.
2. Molecules cannot be created or destroyed in a chemical reaction.
3. Compounds cannot be created or destroyed in a chemical reaction.
4. Heat cannot be created or destroyed in a chemical reaction.
It's an example of a molecule
Answer:
1. The oxidation half-reaction is: Mn(s) ⇄ Mn²⁺(aq) + 2e⁻
2. The reduction half-reaction is: Ag⁺(aq) + 1e⁻ ⇄ Ag(s)
Explanation:
Main reaction: 2Ag⁺(aq) + Mn(s) ⇄ 2Ag(s) + Mn²⁺(aq)
In the oxidation half reaction, the oxidation number increases:
Mn changes from 0, in the ground state to Mn²⁺.
The reduction half reaction occurs where the element decrease the oxidation number, because it is gaining electrons.
Silver changes from Ag⁺ to Ag.
1. The oxidation half-reaction is: Mn(s) ⇄ Mn²⁺(aq) + 2e⁻
2. The reduction half-reaction is: Ag⁺(aq) + 1e⁻ ⇄ Ag(s)
To balance the hole reaction, we need to multiply by 2, the second half reaction:
Mn(s) ⇄ Mn²⁺(aq) + 2e⁻
(Ag⁺(aq) + 1e⁻ ⇄ Ag(s)) . 2
2Ag⁺(aq) + 2e⁻ ⇄ 2Ag(s)
Now we sum, and we can cancel the electrons:
2Ag⁺(aq) + Mn(s) + 2e⁻ ⇄ 2Ag(s) + Mn²⁺(aq) + 2e⁻
