Answer:
Yes, the process of fossilisation is a continuous one. If the conditions are right, a dead plant or animal will be preserved in the rocks of the future, just as they were in the past.
Explanation:
For a fossil to form, several conditions have to be met. First of all, the animal had to live in the given area! Animals live in many environments on Earth, but not everywhere. The water above many lake bottoms and many areas of the deep ocean bottom are stagnant. The bottom water is never exchanged with surface waters, so the water contains no dissolved oxygen. Animals cannot live without oxygen, so no animals live there. In these situations, the only possibility of fossilization is if a fish or other swimming animal dies in oxygen-rich waters above, sinks down into the stagnant muddy bottom, and is buried by sediments.
Answer: D : A is 3 : 2.
Explanation:
The law of definite proportion is being used here. The law states that a given compound always has the same proportion of its constituent elements by mass.
2a + b = c + 3d
This actually means that, two moles of “a” react with a mole of “b” to produce a mole of “c” and 3 moles of “d”
Using the concept of stoichiometry coefficients of d and a
d:a = 3:2
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.
Answer : Option C) 0.3 mol of Gold.
Explanation : Amongst the options given in the question, 0.3 mol of Au is the greatest in mass in grams.
As 0.3 mol X atomic weight of Au (196.966) = 59.088 grams;
Silver has 0.5 mol X atomic weight of Ag (107.86) = 53.93 grams;
The other options are not relevant as they deal in the atomic range which has mass value very less as compared to the moles of elements.
Therefore, it is clear that Au has the greatest mass amongst the given choices.