Answer: (3)
Medeleev arranged elements in order of increasing atomic weight and similar properties
He noticed that similar elements were grouped together by using this.
Answer:
Anthropocene
Explanation:
Anthropocene epoch is sort of unofficial epoch that scientists have used to describe basically human made impact on geological scale.
here's more info:
https://www.earthsystems.com/the-anthropocene/
Answer:
If a substance undergoes a physical change, then it will retain most of its original properties because no new substance is formed.
If a substance undergoes a chemical change, then it will not retain its original properties because a new substance is formed.
Explanation:
So in shorter words its options 2 and 3
Answer:
element
Explanation:
an element is something made up of only one type of atom
Answer:
2.08 moles (3 s.f.)
Explanation:
number of moles
= number of atoms ÷ Avogadro's constant
Avogadro's constant= 6.022 ×10²³
Thus, number of moles
= 1.25×10²⁴ ÷ (6.022 ×10²³)
= 2.08 moles (3 s.f.)
