C. Formation of a new substance
Pretty sure it’s C- hope this helps❤️
Answer: 4.35%
Explanation:
Scientists estimate that the current composition of gases in the Earth's atmosphere has been stable for the last 200 million years or so.
If the Earth was formed 4,600 million years ago then the percentage of her age that the atmosphere has been in its composition is:
= 200 / 4,600 * 100%
= 4.35%
Answer:
Z
Explanation:
Each shell can contain only a fixed number of electrons: The first shell can hold up to two electrons, the second shell can hold up to eight (2 + 6) electrons, the third shell can hold up to 18 (2 + 6 + 10) and so on.
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List of elements with electrons per shell.
Z 5
Element Boron
No. of electrons/shell 2, 3
Group 13
