Answer:
There is an overall release of energy when bonds form.
Explanation:
There is a general release of energy when bonds form. This energy is called bond energy.
Bond energy is involved in the breakdown or formation of one or more bonds between atoms of a molecule. Atoms bond with each other to achieve their electronic stability, that is, they move from a higher energy situation to a lower energy one. With this we can state that when the bond between atoms is formed, energy is released; therefore, its breakdown depends on energy absorption.
The result of Rutherford's gold foil experiment was that most of the particles went straight through the foil without being deflected.
However, a few of the particles were deflected by relatively large angles.
Answer:
a) the final kilocalories per gram for food will be less because the mass was reduced
b)the final kilocalories per gram for food will be less since
c) the final kilocalories per gram for food will be less since the reaction will eventually go to completion
d) the final kilocalories per gram for food will be more.
Explanation:
a) the final kilocalories per gram for food will be less because the mass was reduced from 110.3 to 101.3g
b)the final kilocalories per gram for food will be less since some marshmallow fell off before the reaction
c) the final kilocalories per gram for food will be less since the reaction will eventually go to completion
d) the final kilocalories per gram for food will be more since the thermometer that got stuck will add to the value of final kilocalories per gram
Answer:
1. 0.338 moles of Fe
2. 0.700 moles of Fe
3. 48.3%
Explanation:
This is the reaction:
Fe₂O₃ + 3C → 2Fe + 3CO
We were told that we produce 18.9 g of Fe. Let's convert the mass to moles:
18.9 g . 1mol/ 55.85 g = 0.338 moles of Fe
Let's make a rule of three; ratio is 1:2.
1 mol of oxide can produce 2 moles of elemental iron
Then, 0.350 moles must produce (0.350 .2) / 1 = 0.700 moles of Fe
Let's determine the percent yield:
(Yield produced /Theoretical Yield) . 100 = 48.3 %
Magic number is any number in electron shells that suggest stability. It corresponds to total number of electrons in filled electron shells.
If an electron is having magic number, then it forms stable bonds.
Explanation:
The magic numbers are 2,10,18,36,54, 86 and 126. This refers to the total number of electrons that an electron can have when it is completely filled.
Atomic nuclei which carries either of these nucleons have high binding energy as compared to others. Hence, they have high stability. Bonds in such elements are more strong.
Radioactive decay of such elements is very slow.
Eugene Winger coined the term "magic number".