Well, knowing that group 2A elements are metals, and metals lose electrons to gain a full electron shell, we can eliminate B and D. Knowing that these are 2 electrons, that the group 2A element provides to another atom, to form an ion.
The solution is C. Lose 2 electrons.
To get moles. divide mass by molar mass.Molar mass of
Na is 23
and for Cl is 35.5.
the total molar mass of NaCl is 23+35.5 = 58.5mol/gUse the mass and divide by this number30.22g divide by 58.5mol/g and you will get 0.5166 mole.
Since the molecule has 1 Na to 1 Cl, and that the number of moles for NaCL is 0.5166. All of them would be 0.5166molesNa = 0.5166 x 1 = 0.5166molesCl = 0.5166 x 1 = 0.5166moles
to get number of atoms. Multiply your mole by Avogadro number which is 6.022x10^23Na = 0.5166 x 6.022E23 = 3.111x10^23Cl = 0.5166 x 6.022E23 = 3.111x10^23
Speed is actually instantaneous speed, the speed an object is moving at that very instant.
But average speed is the total distance traveled divided by the total time.
Let's say you travelled 10 miles in 2 hours, your average speed would be 10 divided by 2, which is 10 miles / hr.
But during those 10 miles you may be accelerating, decelerating and be travelling 1 mile/hour and 20 miles/hour at another point. But your average speed would be total distance / total time. So your instantaneous speed can change throughout that period of time.
I think it's 2 I tried looking it up because I was not sure.