Answer:
Explanation:
The formula for the heat released is
q = mCΔT
Data:
m = 28.9 g
C = 0.385 J·°C⁻¹g⁻¹
T₁ = 1083 °C
T₂ = 25.0 °C
Calculations:
(a)Temperature change
ΔT = T₂ - T₁ = 25.0 - 1083 = -1058 °C
(b) Heat released
q = 28.9 × 0.385 × (-1058) = -11 800 J = -11.8 kJ
The negative sign shows that energy is released, so the copper has released of energy.
Answer:
CH3OH > CH3Cl > CH4
Explanation:
The boiling point of a compound depends on the nature and magnitude of intermolecular forces acting between its molecules.
Methanol contains the -OH group, hence hydrogen bonds are dominant intermolecular forces in the compound. Presence of hydrogen bonds increases the boiling point of a substance, hence methanol has the highest boiling point followed by chloromethane which has dipole-dipole interaction as dominant intermolecular forces and methane having only weak dispersion forces as dominant intermolecular forces.
Answer is: Maria's chemical analysis is not correct.
Sucrose is only dissolved in water, there are still sucrose molecules in solution, not molecules of fructose and glucose. For breaking bonds in molecule of sucrose enzymes are needed.
Solution is homogeneous mixture composed of two or more substances.
In aqueous solution, solvent is water and solute (in this example sucrose) is a substance dissolved in water.
Homogeneous solution of sugar and water can be separated with heating (evaporating the water).