Answer:
Examples of chemical changes are burning, cooking, rusting, and rotting. Examples of physical changes are boiling, melting, freezing, and shredding. Often, physical changes can be undone, if energy is input.
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Answer:
3.7 mol O₃
Explanation:
Step 1: Write the balanced equation
2 O₃ ⇒ 3 O₂
Step 2: Establish the appropriate molar ratio
According to the balanced equation, the molar ratio of O₃ to O₂ is 2:3.
Step 3: Calculate the number of moles of O₃ required to produce 5.5 moles of O₂
We will use the previously established molar ratio.
5.5 mol O₂ × 2 mol O₃/3 mol O₂ = 3.7 mol O₃
Answer : The concentration of ion is,
Solution : Given,
pH = 4.20
First we have to calculate the pOH.
As we know that,
Now we have to calculate the concentration of ion.
Therefore, the concentration of ion is,
E=hc/λ =6.626×10^-34×3 ×10^8 / 3×10^7 × 10^-9 = 6.626×10 ^-24J.
Answer:
x = 100 * 1.1897 = 118.97 %, which is > 100 meaning that all of the HClO2 dissociates
Explanation:
Recall that , depression present in freezing point is calculated with the formulae = solute particles Molarity x KF
0.3473 = m * 1.86
Solving, m = 0.187 m
Moles of HClO2 = mass / molar mass = 5.85 / 68.5 = 0.0854 mol
Molality = moles / mass of water in kg = 0.0854 / 1 = 0.0854 m
Initial molality
Assuming that a % x of the solute dissociates, we have the ICE table:
HClO2 H+ + ClO2-
initial concentration: 0.0854 0 0
final concentration: 0.0854(1-x/100) 0.0854x/100 0.0854x / 100
We see that sum of molality of equilibrium mixture = freezing point molality
0.0854( 1 - x/100 + x/100 + x/100) = 0.187
2.1897 = 1 + x / 100
x = 100 * 1.1897 = 118.97 %, which is > 100 meaning that all of the HClO2 dissociates