Answer:
bromine will be replaced by fluorine.
Explanation:
lithium bromide LiBr2 is an ionic compoung splitting as Li2+ and Br-
therefore bromide ion is replaced by fluoride ion F-.
The molar mass of Calcium hydroxide is 74 g/mol
To find the percent composition we have to find the number of atoms of each element in the formula .
So there’s
Calcium - 1
Oxygen - 2
Hydrogen - 2
Then have to multiply the relative atomic mass of each element by the number of atoms
Ca - 40 g/mol x 1 = 40
O - 16 g/mol x 2 = 32
H - 1 g/mol x 2 = 2
Then To find percent composition of each element we have to divide the mass of each element in the formula by the relative molecular mass of calcium hydroxide
Ca - 40 / 74 x 100 % = 54.0%
O - 32 / 74 x 100 % = 43.2 %
H - 2 / 74 x 100 % = 2.7%
From the options given correct answer is 3rd option
54.0% Ca , 43.0% O and 2.7 % H
Answer:
molecular weight (Mb) = 0.42 g/mol
Explanation:
mass sample (solute) (wb) = 58.125 g
mass sln = 750.0 g = mass solute + mass solvent
∴ solute (b) unknown nonelectrolyte compound
∴ solvent (a): water
⇒ mb = mol solute/Kg solvent (nb/wa)
boiling point:
- ΔT = K*mb = 100.220°C ≅ 373.22 K
∴ K water = 1.86 K.Kg/mol
⇒ Mb = ? (molecular weight) (wb/nb)
⇒ mb = ΔT / K
⇒ mb = (373.22 K) / (1.86 K.Kg/mol)
⇒ mb = 200.656 mol/Kg
∴ mass solvent = 750.0 g - 58.125 g = 691.875 g = 0.692 Kg
moles solute:
⇒ nb = (200.656 mol/Kg)*(0.692 Kg) = 138.83 mol solute
molecular weight:
⇒ Mb = (58.125 g)/(138.83 mol) = 0.42 g/mol
A Watt is usually used to measure the amount of electrical energy used in a home
