The following are the statements, which indicates that the fossil record suggests about evolution on Earth:
1. Humans have only recently existed on Earth.
2. The organisms originally lived only in Earth's water.
3. The plants did not have flowers when dinosaurs existed.
The fossil remains have been discovered in the rocks of all the ages. The simplest organisms fossils are witnessed in the oldest rocks, and the fossils of more composite species are found in the newest rocks. This supports the theory of evolution suggested by Darwin, according to which the simple life forms slowly gets evolved into more composite ones.
<span>To convert the number of moles a compound to formula units, the conversion factor is Avogadro's number, 6.022 x10^23 formula units/ mol. In this case, we are given with 7.02 moles of sodium chloride. Hence the answer is 4.23 x 10^24 formula units.</span>
Answer:
see notes below
Explanation:
The mole is the mass of substance containing 1 Avogadro's Number of particles. That is, 1 mole substance = 1 formula weight. For elements, 1 mole weight is equal to the atomic weight expressed as grams. For molecules, 1 mole weight is equal to the molecular weight expressed as grams.
1 mole = 1 formula weight
<u>Moles to Grams and Grams to Moles</u>
Grams => Moles
Given grams, moles = mass given / formula weight
*Ask the question => How many formula weights are there in the given mass? => Results is always moles.
Moles => Grams
Given moles, grams = moles given X formula weight
*Summary
Grams to Moles => divide by formula weight
Moles to Grams => multiply by formula weight
The postulate of Dalton's atomic theory which is a result of the law of conservation of mass is: Atoms are indivisible particles, which can neither be created nor destroyed in a chemical reaction.