<u>Answer:</u>
<em>False</em>
<em></em>
<u>Explanation:</u>
The energy required to break a bond is endothermic that is energy is absorbed to break a bond.
The energy is released in the formation of a bond that is energy is released when a bond is formed.
The formula to find the ∆H of the reaction is
∆H (reaction) = ∆H (bonds Broken) - ∆H (bonds formed)
For example
contains one N ≡ N triple bond (Bond breaking 946 KJ per mol)
contains a single H-H bond (bond breaking 436KJ per mol)
contains 3 N-H single bonds (389 KJ per mol)
So,
∆H (bonds broken) = 946 + (3 × 436) = 2254 KJ
∆H (Bonds formed ) = (2 × 3 × 389) = 2334 KJ
So,
∆H (reaction) = 2254 KJ - 2334 KJ = - 80 KJ
The reaction is Exothermic
In this example we see energy required to break the bond is lesser than energy released in forming the bond.
So we can conclude if the amount of energy required to break bonds in the reactants is more than the amount of energy released in forming bonds in the products, then the reaction will have a positive change in enthalpy and ∆H is positive (+∆H) .
I think the correct answer would be false. The atomic mass of chlorine does not represent the mass of the most common naturally occurring isotope of chlorine. The atomic mass of any compound is the average of the atomic masses of the naturally occurring isotopes of an element. <span />
This process involves the dilution of the 12 molar HCl. To reduce the concentration, we need to set up an equality so that we know how much of the 12M we need to make the 3.5M.
12 moles HCl 3.5 moles HCl
——————— = ———————
1 Liter of Soln ‘x’ Liters of Soln
Notice that the 12 moles over the 1 liter is equal to 12 molar; in doing this, we’re maintaining the concentration of the initial HCl. By setting it equal to the 3.5 over ‘x’, we’re still maintaining the concentration.
After solving, we find that ‘x’ equals 0.292. This value means that in 0.292 liters of our 12 M HCl solution, there are 3.5 moles of HCl. But, we’re not done yet.
0.292 liters of 12 M HCl can make 1 liter of 3.5 M HCl, but the question asks for 1.5 liters. To get this, multiply 0.292 liters by 1.5, and the new result, 0.4375, represents the amount of 12 M HCl required to prepare a 1500 mL 3.5 M HCl solution.
It's -Bohr's Model- becuase Dalton I dont think did a model. Thomson's was the "Plum Pudding Model." Ernest Rutherford drew one out(I dont know i dont have a model down though) so it the only one left is Dalton's Model which is it. (Hopefuly)
