Among the choices, the unit of energy is calories. Answer in 1) is D. In 2) we are given with te mass , heat and temperature change. we just need to get the heat capacity and compare it with the following metals. The calculated heat capacity is 0.46 kJ/kg K. The answer is A. iron. In 3) we can compute the heat absorbed by the formula ΔH=mCpΔT. Cp of water is 4.18 J/g K. Answer of 3) is D. In 4) the formula used in Cp=ΔH/mΔT. Answer in 4) is A. The heat of enthalpy of fusion of ice is 80 cal/g. We convert this to J/g. Answer in 5) is B.334 J/g.
Answer:
the last answer is right.
Answer:
Magnesium + iron chloride → iron + magnesium chloride
Explanation:
It is the single replacement reaction.
Single replacement:
It is the reaction in which one elements replace the other element in compound.
AB + C → AC + B
Molecular equation:
Magnesium + iron chloride → iron + magnesium chloride
Chemical equation:
Mg(s) + FeCl₂(aq) → MgCl₂(aq) + Fe(s)
Ionic equation:
Mg(s) + Fe²⁺(aq) + 2Cl⁻(aq) → Mg²⁺(aq) + 2Cl⁻(aq) + Fe(s)
Net ionic equation:
Mg(s) + Fe²⁺(aq) → Fe(s) + Mg²⁺(aq)
Answer:
a) 1512000 Joules
b) 5040 seconds = 84 minutes = 1.4 hours
Explanation:
Power saved y replacing bulbs = 60-18 = 42 W = 42 J/s
Time the bulb is used for = 10 hours
Energy saved during this time
42×10×60×60 = 1512000 Joules
Saved energy by replacing standard incandescent lightbulbs with energy-efficient compact fluorescent lightbulbs in 10 hours is 1512000 Joules
b) Power the plasma TV uses = 300 W = J/s
\frac{1512000}{300}=5040\ s3001512000=5040 s
Time a plasma TV can be used for with the saved energy is 5040 seconds = 84 minutes = 1.4 hours.
