Author Question: Physical Science: How much heat is necessary to change 205 g of ice at -6°C to w (Read 1653 times)

lb_gilbert

  • Hero Member
  • *****
  • Posts: 588
How much heat is necessary to change 205 g of ice at -6°C to water at 20°C?



sammy

  • Hero Member
  • *****
  • Posts: 818
Hi lb_gilbert.

I'm not a chemistry expert, but I did find a similar question with a solution attached:

Two 20.0-g ice cubes at –17.0 °C are placed into 255 g of water at 25.0 °C. Assuming no energy is transferred to or from the surroundings, calculate the final temperature of the water after all the ice melts.

Answer

∆T for ice = (0 - (-17)) = +17 ºC
∆T for the water from the ice = (T - 0) - T ºC
∆T for the initial water only = (T - 25)

Heat quantity Q change for the ice = mol(ice)*cp(ice)*17 + enthalpy of fusion*mol(ice) + mol(ice)*cp(water)*T

Heat quantity Q change for the water = m0l(water)*cp(water)*(T - 25)

molar mass H2O = 18g/mol so 40g ice = 2.22 mol(ice) and 255 g water = 15.3 mol(water)

2.22*37.7*17 + 2.22*6010 + 2.22*75.3*T + 15.3*75.3*(T - 25) = 0

14740 + 167.2*T + 1152*T - 28802 = 0

1389*T = 14062

T = 10.1 ºC

Looking forward to more questions and your response!



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

Increased intake of vitamin D has been shown to reduce fractures up to 25% in older people.

Did you know?

In the ancient and medieval periods, dysentery killed about ? of all babies before they reach 12 months of age. The disease was transferred through contaminated drinking water, because there was no way to adequately dispose of sewage, which contaminated the water.

Did you know?

Allergies play a major part in the health of children. The most prevalent childhood allergies are milk, egg, soy, wheat, peanuts, tree nuts, and seafood.

Did you know?

Adults are resistant to the bacterium that causes Botulism. These bacteria thrive in honey – therefore, honey should never be given to infants since their immune systems are not yet resistant.

Did you know?

Illness; diuretics; laxative abuse; hot weather; exercise; sweating; caffeine; alcoholic beverages; starvation diets; inadequate carbohydrate consumption; and diets high in protein, salt, or fiber can cause people to become dehydrated.

For a complete list of videos, visit our video library