Ahot lump of 115.7 g of an unknown substance initially at 168.3°c is placed in 25.0 ml of water initially at 25.0°c and allowed to reach thermal equilibrium. the final temperature of the system is 76.5°c. what is the identity of the unknown substance? assume no heat is lost to the surroundings

The substance has the specific heat capacity of steel and is therefore probably steel.  

Let the specific heat of the unknown lump of substance be .

Energy Exchange = Specific Heat ⨯ Mass ⨯ Temperature Change

Energy the Hot Lump Lost = Energy the Cold Water Gained

Water has a specific heat of and a density of . 25.0 milliliters of water thus has a mass of 25.0 grams.

Steel has a specific heat of approximately . This substance is thus probably steel.

The specific heat capacity of the substance: 509.18 J / Kg.K, which approaches the specific heat capacity of metals table chart is Steel, Mild

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

Heat can be calculated using the formula:

An unknown substance is  placed in 25.0 mL of water and there will be heat transfer:

m = substance

w = water

T = the final temperature of the mixture

A hot lump of 115.7 g of an unknown substance initially at 168.3 ° C is placed in 25.0 mL of water initially at 25.0 ° C and allowed to reach thermal equilibrium. The final temperature of the system is 76.5 ° C

known:

m of substance = 115.7 g = 0.1157 kg

Tm = 168.3 ◦C + 273 = 441.3 K

m of water = 25 ml = 25 g = 0.025 kg

Tw = 25 ◦C + 273 = 298 K

cw = 4,200 J / kg C

T = 76.5 + 273 = 349.5 K

the specific heat capacity of the substance:

the difference between temperature and heat

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Specific heat

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relationships among temperature, heat, and thermal energy.

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When heat is added to a substance

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Keywords: heat, temperature, thermal equilibrium

the earth would become to overheated and everything alive on it will eventually die from overheating. plants will eventually die as well, water will evaporate, and it will be nothing but a hot planet without anything living on it.