A sample of aluminum, which has a specific heat capacity of , is dropped into an insulated container containing of water at and a constant pressure of . The initial temperature of the aluminum is . Assuming no heat is absorbed from or by the container, or the surroundings, calculate the equilibrium temperature of the water. Be sure your answer has significant digit

The answer is below

Explanation:

A 21.0 g sample of aluminum, which has a specific heat capacity of 0.897 J g '°C ', is dropped into an insulated container containing 200.0 g of water at 25.0 °C and a constant pressure of 1 atm. The initial temperature of the aluminum is 90.1 °C Assuming no heat is absorbed from or by the container, or the surroundings, calculate the equilibrium temperature of the water. Be sure your answer has 3 significant digits.

Solution:

The amount of heat lost or gained by a substance is given by the formula:

Q = mcΔT

Where Q is the heat lost or gained, m is the mass of the substance, ΔT is the temperature change.

The law of conservation of energy states that energy cannot be created or destroyed but can be transferred.

Therefore the heat lost by aluminum = heat gained by water

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2