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4 years ago

Please help!

Chemistry

1 answer:

lyudmila [28]4 years ago

4 0

<h3>The equation</h3>

4.94 x c . (Tm-23.6)=C.(23-6-21.9)+123.13 x c. (23.6-21.9)

<h3>Further explanation </h3>

The law of conservation of energy can be applied to heat changes, ie the heat received/absorbed is the same as the heat released

Q in = Q out

Heat can be calculated using the formula:

Q = mc∆T

A calorimeter is a device used to measure the specific heat of material

A metal is put into a calorimeter that contains water and there will be heat transfer:

$\tt \displaystyle m_mc_m (T_m-T)=m_wc_w(T-Tw)$

m = metal

w = water

T = the final temperature of the mixture

mass of metal =(Nickel) = 4.94 g

mass of calorimeter = 12.5 g

mass of water = 123.13 g (135.63 - 12.5)

The equation

Q released (metal) = Q absorbed(calorimeter+water)

Qmetal = 4.94 x c . (Tm-23.60)
Q calorimeter = C.(23-6-21.9) --> C = heat capacity of calorimeter
Q water = 123.13 x c. (23.6-21.9)

The equation :

4.94 x c . (Tm-23.6)=C.(23-6-21.9)+123.13 x c. (23.6-21.9)

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