The correct answer should be B.
The correct answer would be B.
Capture all of the smoke and weight it. it will weigh exactly the same before and after you burn it but will just be CO2 and H2O gas.
Answer:
for given question is 2.79 and
is 0.52
{i- vant hoff’s constant ; Kb- constant ; m molarity }
M = no. of moles of the solute present in one kg of solution
Let the weight of amount of solute be “w” and its molecular mass be “M”
Let the mass of the solvent in the given question be “x”




Answer:
01) Cu tting hair is a physical change. reason-1
02) Cooking can be either one, but I would choose chemical reason-3
03) Ice cream melting is a physical change reason-2
Explanation:
Answer:
75.15 mol.
Explanation:
- Firstly, we need to write the balanced equation of the reaction:
<em>Fe₂O₃ + 3CO → 2Fe + 3CO₂.</em>
It is clear that 1.0 mole of Fe₂O₃ reacts with 3.0 moles of CO to produce 2.0 moles of Fe and 3.0 moles of CO₂.
∴ Fe₂O₃ reacts with CO with (1: 3) molar ratio.
- we need to calculate the no. of moles of (4000 g) of Fe₂O₃:
<em>no. of moles of Fe₂O₃ = mass/molar mass</em> = (4000 g)/(159.69 g/mol) = <em>25.05 mol.</em>
<u>Using cross multiplication:</u>
1.0 mole of Fe₂O₃ needs → 3.0 moles of CO,
∴ 25.05 mole of Fe₂O₃ needs → ??? moles of CO.
<em>∴ The no. of moles of CO needed</em> = (3.0 mol)(25.05 mol)/(1.0 mol) =<em> 75.15 mol.</em>