Answer: Ice is melting due to the transfer of thermal energy from Jan's hand to ice.
Explanation: The melting of ice is a physical change and is happening when the thermal energy from Jan's hand is transferred to ice. Due to this energy transfer, the particles of ice starts to move faster and hence, making the ice melt.
In this, the physical state of ice is changing from solid to liquid state.
Check attached file for the answer.
<span>Answer:
Enthalpy Change = (6 x -393.5) + (7 x -285.8) - (-204.6) + (19/2) 0.....???
like.. (6 x Enth CO2) + ( 7 x Enth H2O) - (Enth C6H14) + (19/2) Enth O2</span>
Answer:
The answer is 465.6 mg of MgI₂ to be added.
Explanation:
We find the mole of ion I⁻ in the final solution
C = n/V -> n = C x V = 0.2577 (L) x 0.1 (mol/L) = 0.02577 mol
But in the initial solution, there was 0.087 M KI, which can be converted into mole same as above calculation, equal to 0.02242 mol.
So we need to add an addition amount of 0.02577 - 0.02242 = 0.00335 mol of I⁻. But each molecule of MgI₂ yields two ions of I⁻, so we need to divide 0.00335 by 2 to find the mole of MgI₂, which then is 0.001675 mol.
Hence, the weight of MgI₂ must be added is
Weight of MgI₂ = 0.001675 mol x 278 g/mol = 0.4656 g = 465.6 mg
Answer:
2 electrons are transfered in this reaction.
Explanation:
Oxidation is a reaction where an atom, ion, or molecule loses electrons, while reduction corresponds to the electron gain of an atom, ion, or molecule.
In an oxidation-reduction reaction two simultaneous processes take place, oxidation and reduction.
So, oxidation-reduction (redox) reactions involve the transfer of electrons between chemical species. They are also called electron transfer reactions since the particle that is exchanged is the electron.
In this case:
Zn(s) ⇒ Zn²⁺(aq) + 2 e⁻
2 Ag⁺ (aq) + 2 e⁻ ⇒ 2 Ag(s)
So, zinc metal loses two electrons to form the zinc(II) ions, while the two silver ions each gain one electron to form two silver metal atoms.
Then, Zn is a reducing agent (The reducing agent is the one that provides the electrons, oxidizing itself), AgNO3 is an oxidizing agent (The oxidizing agent is the one that traps the electrons, reducing itself).
Finally, you can see that <u><em>2 electrons are transfered in this reaction.</em></u>
