Question

Write the Atomic mass for the following elements. 1) Silicon 11) Magnesium 111) Fluorine iv) Lithium​

Answer 1

Seeing chemical elements arranged in the modern periodic table is as familiar as seeing a map of the world, but it was not always so obvious.

The creator of the periodic table, Dmitri Mendeleev, in 1869 began collecting and sorting known properties of elements, like he was playing a game, while traveling by train. He noticed that there were groups of elements that exhibited similar properties, but he also noticed that there were plenty of exceptions to the emerging patterns.

Incredibly, instead of giving up, he tried altering the measured property values to better fit the patterns! He also predicted that certain elements must exist which didn’t at the time – again, in an effort to get the patterns in his "game" to work out.

There were plenty of skeptics and it took years to gain international acceptance, but once newly-discovered elements matched the ones that Mendeleev predicted, his patterns could not be dismissed. In addition, some of the properties that he "fudged" were later recalculated and found to be much closer to his predictions.

Explanation:

Answer 2

Answer:

1. Si- 28.0855 u

Atomic number: 14

2. Mg- 24.305 u

Atomic number: 12

3. F- 18.998403 u

Atomic number: 9

4. Li- 6.941 u

Atomic number: 3