Answer:
130 g of sucrose
Explanation:
Boiling point elevation formula → ΔT = Kb . m
ΔT = Boiling T° solution - Boiling T° pure solvent → 0.39°C
0.39°C = 0.513°C/m . M
m = 0.760 mol/kg → molality = moles of solute / 1kg of solvent
Let's determine the moles of solute → molality . kg
0.760 mol/kg. 0.5 kg = 0.380 moles
If we convert the moles to mass, we'll get the answer
0.380 mol . 342.30 g/mol = 130g
Let's use the example: H2O ---> H2 + O2
We find how many elements of a product are on one side and how many elements on the other side.
Reactant: H=2 O=1
Product: H=2 O=2
We need to make the same amount of hydrogen and oxegyn atoms on each side, regardless of how high the numbers are, and we do this by adding coefficients to the compounds.
Reactant: H=4 O=2
Product : H=4 O=2
2 H2O---> 2 H2 + O2
The theoretical proportion is given by the balanced chemical equation:
2 mol NBr / 3 mol Na OH
Then x mol NaOH / 40 mol NBr3 = 3mol NaOH/2 mol NBr3
Solve for x, x = 40 * 3/2 = 60 mol NaOH.
Given that there are 48 mol NaOH (less than 60) this is the limitant reactant and the other is the excess reactant.
Answer: NBr3..
Density is Mass divided by volume.
Answer:
55
Explanation:
25g is less dense than 80g therefore will mostly float. if you subtract 80-25 that will leave you will 55 as the difference
