Scientists should control most possible variables in experiments to get the most valid and correct data. If many variables are included in experiments it is more difficult to interpret what is causing a different outcome.
We know that domestic dogs are descended from wolves. Exactly when and how this occurred is still being studied; many experts indicate that dogs were first domesticated about 12,000 years ago, but a few DNA studies indicate a much earlier date for the split between the wolf and the dog, perhaps as long ago as 130,000 years.
Regardless of the exact timing of the divergence between wolves and dogs, one thing is true: both species display quite a bit of genetic diversity, particularly in size and coloration.In order to breed a dog of a specific size, all one has to do is choose parents with the appropriate variations. For instance, if you want to create a small dog breed, you would just breed the smallest dogs you have, then you would choose their smallest offspring to breed the next generation, and so on until you have reached the desired size.
Answer:
The correct answer is Pu, 234.
Explanation:
In the given case, let us consider the reactant as X. Now the mass number (balanced) on both the sides will be,
Mass of X = Mass of Molybdenum + Mass of Tin + Mass of neutrons
M = 1 * 103 + 1 * 131 + 2 * 0
M = 234
Now the atomic number (balanced) on both the sides,
Atomic number of X = Atomic number of Molybdenum + Atomic number of Tin + Atomic number of neutrons
A = 1*42 + 1*50 + 2*1
A = 94
The atomic number 94 is for the element Plutonium, whose symbol is Pu. Thus, the reactant is 234-Pu.
4.06x20^24/6.02x10^23 = 6.744 moles x 55.845 g/mole = 376.61868grams
