Responder:
27
Explicación:
Dado que:
Número de protones en el átomo X = 29
Carga en el átomo X = +2
Si no hay cargo neto;
número de protones = número de electrones
Sin embargo, dado que el átomo X tiene una carga de +2 (dando 2 electrones).
Por lo tanto,
Número de electrones = número de protones - número de carga en el átomo)
Número de electrones = (29 - 2) = 27
C. Accelerating should be the correct onw
Volume of solute = 250 * 2%
= 250 * 0.02
= 5
In short, Your Answer would be 5 mL
Hope this helps!
Answer:
molality of sodium ions is 1.473 m
Explanation:
Molarity is moles of solute per litre of solution
Molality is moles of solute per kg of solvent.
The volume of solution = 1 L
The mass of solution = volume X density = 1000mL X 1.43 = 1430 grams
The mass of solute = moles X molar mass of sodium phosphate = 0.65X164
mass of solute = 106.6 grams
the mass of solvent = 1430 - 106.6 = 1323.4 grams = 1.3234 Kg
the molality = 
Thus molality of sodium phosphate is 0.491 m
Each sodium phosphate of molecule will give three sodium ions.
Thus molality of sodium ions = 3 X 0.491 = 1.473 m
First. moles is just a label for a number of things. just like a
dozen = 12, a gross = 144, a mole = 6022 with another 20 zeros after the
2
next
moles = mass / molecular weight.
molecular weight = sum of atomic mass from the periodic table
atomic mass MnO2 = atomic mass Mn + 2 x atomic mass O
= 54.94 + 2 x 16 = 86.94 g/mole
so moles MnO2 = 98.0 grams / (86.94 g/mole) = 1.13 moles
notice that I only gave 3 digits? that because of sig figs read the link below if you don't understand....
mw C5H12 = 5 x 12 + 12 x 1 = 72 g/mole
so moles C5H12 = 12.0 g / 72.0 g/mole = 0.167 moles
mw XeF6 = 131.3+ 6 x 19.00 = 245.3
so moles XeF6 = 100 g / 245.3 g/mole = 0.4077 moles
I've also provided a link to a periodic table. if you need atomic weights click on any element and it will give you the
details.
