Answer:
The molar mass (Mm) of the compound is 127.39 g/mole
Explanation:
ΔT = Kf. molality
ΔT = change in temperature = Tfinal - Tinitial = 2.8 - 5.5
Kf = freezing point depression constant = - 4.3 C/m (always negative because temperature is decreasing)
molality = moles of solute/Kg of solvent = mole (n)/(20 x 10^-3 Kg of benzene)
(2.8 - 5.5) = (-4.3) x molality
molality = 0.6279 mole/kg
0.6279 = mole of compound/(20 x 10^-3)
mole of compound = 0.01256 mole
mole (n) = mass (m) divided by Molar mass (Mm)
Molar mass = mass of compound / mole of compound
m/n = 1.6/0.01256 = 127.39 g/mole
Answer: hot
Explanation:
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and the system will be cold and surroundings will be hot.
Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and the system will be hot and surroundings will be cold.
As heat is absorbed, the reaction is endothermic and the system will feel hot.
Answer:
6 moles of C atoms, 12 moles of H atoms and 6 moles of O atoms
Explanation:
A chemical formula represents the number of moles of atoms presents in 1 mole of the compound.
For example, for 1 mole:
CₐHₓ, you have a moles of carbon and x moles of hydrogen.
Thus, for the molecule:
C₆H₁₂O₆, you have <em>6 moles of C atoms, 12 moles of H atoms and 6 moles of O atoms</em>
Answer:
0.363 g
Explanation:
2As + 3Cl₂ → 2AsCl₃
calculate the number of moles of arsenic
Number of moles = mass/ molar mass
Number of moles = 0.150 g/ 75 g/mol
Number of moles = 0.002 mol
compare the moles of arsenic with arsenic chloride.
As : AsCl₃
2 : 2
0.002 : 0.002
Mass of arsenic chloride produced:
Mass = number of moles × molar mass
Mass = 0.002 × 181.28 g/mol
Mass = 0.363 g
