Answer:

Explanation:
To convert from representative particles to moles, Avogadro's Number: 6.02*10²³, which tells us the number of particles (atoms, molecules, etc.) in 1 mole of a substance.
We can use it in a ratio.

Multiply by the given number of molecules.

Flip the ratio so the molecules of water cancel out.



Divide.

The original number of molecules has 2 significant figures: 3 and 1, so our answer must have the same. For the number we calculated, that is the tenth place. The 4 in the hundredth place tells us to leave the 1.

There are about 5.1 moles of water in 3.1*10²⁴ molecules of water.
Answer:
The atom is divisible particle and can be subdivided into smaller particles proton, neutron and electrons was not stated by John dalton.
Explanation:
The postulate of Dalton's atomic theory that atom is indivisible particle and can not be subdivided into smaller particles was later changed because atom can be divided into neutrons, protons and electrons.
Electron:
The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.
Symbol= e⁻
Mass= 9.10938356×10⁻³¹ Kg
It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.
Proton and neutron:
While neutron and proton are present inside the nucleus. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.
Symbol of proton= P⁺
Symbol of neutron= n⁰
Mass of proton=1.672623×10⁻²⁷ Kg
Mass of neutron=1.674929×10⁻²⁷ Kg
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron.
FALSE
Organisms may play only one role in an ecosystem. ... Each of the organisms in an ecosystem fills the energy role of producer, consumer, or decomposer.
~~~~iln~~~~~~
+2, because Beryllium is in the Group II of the periodic table.
Hope this helps!