The number is written in scientific notation.
The significant figures are the numbers known precisely plus 1 digit that is uncertain.
When the numbers are expressed in scientific notation all the digits before 10^n are significant.
So, 7 and 8 are significant figures and the answer is that the number of significant figures is 2.
Answer: 2
1 mol of Silicon = 28.0855 g (in average)
then
1 mol = 6.022*10^23 atoms
then
28.0855/(6.022*10^23) g/atom
4.66381*10^-23 g per atom
The correct answer is A. All electrons become free and separate from the nuclei. In metallic bonds, the electrons of the metal atoms are delocalized. The electron in the electron sea can freely roam around or are free to flow.
As iron heats up, the arrangement of its atoms changes several times before it melts. ... Iron is magnetic at room temperature, and previous work predicted that iron's magnetism favors its open structure at low temperatures, but at 770 degrees Celsius iron loses its magnetism.
plz mark me as brainliest if this helped
Answer:
All elements in the same group of the periodic table have the same number of valence electrons. This made it possible to compare the valence of the alien elements to the valence of elements from our periodic table, and match the alien elements to the correct group. For example, our group 14 elements all have 4 valence electrons, so the alien element with 4 valence electrons had to be part of group 14 also.
