21Explanation:BEACUSE I CAN
Answer:
CRYSTAL
MANY ATOMS THAT ARE ARRANGE IN A REGULAR PATTERN
1:1
Explanation:
atomic mass=percentage of isotope a * mass of isotope a + percentage of isotope b * mass of isotope b+...+percentage of isotope n * mass of isotope n.
Data:
mass of isotope₁=267.8 u
percentage of isotope₁=90.3%
mass of isotope₂=270.9 u
percentage of isotope₂=9.7%
Therefore:
atomic mass=(0.903)(267.8 u)+(0.097)(270.9 u)=
=241.8234 u + 26.2773 u≈268.1 u
Answer: the mass atomic of this element would be 268.1 u
Answer:
4.52 mol/kg
Explanation:
Given data:
Mass of lithium fluoride = 22.1 g
Mass of water = 188 g
Molality = ?
Solution:
Molality:
It is the number of moles of solute into kilogram of solvent.
Formula:
Molality = number of moles of solute / kilogram solvent
Mathematical expression:
m = n/kg
Now we will convert the grams of LiF into moles.
Number of moles = mass/ molar mass
Number of moles = 22.1 g/ 26 g/mol
Number of moles = 0.85 mol
Now we will convert the g of water into kg.
Mass of water = 188 g× 1kg/1000 g = 0.188 kg
Now we will put the values in formula.
m = 0.85 mol / 0.188 kg
m = 4.52 mol/kg
Answer: The mole ratio of sodium to sodium chloride 2:2.
Explanation:
As the given reaction equation is as follows.

Here, 2 moles of sodium reacts with 1 mole of
and leads to the formation of 2 moles of NaCl.
This means that 2 moles of sodium gives 2 moles of NaCl on reaction with chlorine.
Hence, the ratio of moles of sodium to sodium chloride is 2:2.
Thus, we can conclude that the mole ratio of sodium to sodium chloride 2:2.