Answer:
0.18× 10²³ molecules
Explanation:
Given data:
Mass of copper hydroxide = 3.30 g
Number of molecules = ?
Solution:
Number of moles = mass/molar mass
Number of moles = 3.30 g/97.56 g/mol
Number of moles = 0.03 mol
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ molecules
0.03 mol × 6.022 × 10²³ molecules / 1mol
0.18× 10²³ molecules
The amount, in mL, of the concentrated acid required, would be 1.1875 mL
<h3>Dilution</h3>
From the dilution equation:
m1v1=m2v2 where m1 and m2 = molarity before and after dilution, and v1 and v2 = volume before and after dilution.
m2 = 0.285M, m1 = 12.0M v2 = 50.0 mL
v1 = m2v2/m1 = 0.285x50/12 = 1.1875 mL
Thus, 1.1875 mL of the acid would be taken and diluted with water up to the 50 mL mark.
More on dilution can be found here: brainly.com/question/13949222
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Answer : The value of
for this reaction is 36.18 kJ
Explanation :
First law of thermodynamic : It states that the energy can not be created or destroyed, it can only change or transfer from one state to another state.
As per first law of thermodynamic,

where,
= internal energy of the system
q = heat added or rejected by the system
w = work done
As we are given that:
q = 38.65 kJ
w = -2.47 kJ (system work done on surrounding)
Now put all the given values in the above expression, we get:


Therefore, the value of
for this reaction is 36.18 kJ
It is very camouflaged this way it will survive longer then most other animals
Generally, chemists prefer to use morality (B) because it only invovles measuring the final volume of the solution and amount of moles of the solute
Hope this helps