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4 years ago

What is the variable for the quantity of heat in a system?

Chemistry

1 answer:

Crank4 years ago

8 0

Answer:

The heat capacity is the amount of heat, expressed usually in Joules or calories, needed to change the system by 1 degree Celsius. The specific heat capacity is the amount of heat required to raise 1 gram of a substance by 1 degree Celsius.

Explanation:

For example, the specific heat of H2O(l) is 4.18 J/g ° C.

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HELP NOW!!!!!! When you put water into a hot metal pan of equal mass, why does the pan cool down more than the water heats up?

Salsk061 [2.6K]

Answer:

Because the specific heat of the metal is less than the specific heat of water.

Explanation:

Hello, happy to help you today!

In this case, we need to analyze a property called "specific heat" which accounts for how much energy is required to increase or decrease the temperature of 1 g of the substance by 1 °C.

In this case, since the specific heat of water is about 4.184 J/g°C and the specific heat of metals in general is greater than zero, of course, but less than one, we can infer that for the same amount of energy, when they are in contact, more grams of metal will be cooled down to those of water heated up, because the specific heat of the metal is less than the specific heat of water.

Best regards!.

8 0

3 years ago

Which sample of copper has atoms with the lowest average kinetic energy? 1. 10. g at 45°C 2. 20. g at 35°C 3. 30. g at 25°C 4. 4

blagie [28]

I would say <span>4. 40. g at 15°C because kinetic energy is related to temperature and not mass, so the lower temp would give you lower KE</span>

7 0

3 years ago

Read 2 more answers

Pls help and match them

slega [8]

Answer:

Simile: C

Personification: D

Symbol: A

Hyperbole: B

Metaphor: E

Explanation:

3 0

3 years ago

If a pork roast must absorb kJ to fully cook, and if only 10% of the heat produced by the barbecue is actually absorbed by the r

kolezko [41]

Answer:

1,033.56 grams of carbon dioxide was emitted into the atmosphere.

Explanation:

$C_3H_8(g)+5O_2(g)\rightarrow 3CO_2(g)+4H_2O(g),\Delta H_{rxn}=-2044 kJ/mol (assuming)$

Energy absorbed by pork,E = $1.6\times 10^3 kJ$ (assuming)

Total energy produced by barbecue = Q

Percentage of energy absorbed by pork = 10%

$10\%=\frac{E}{Q}\times 100$

$Q=\frac{E}{10}\times 100=\frac{1.6\times 10^3 kJ}{10}\times 100=1.6\times 10^4 kJ$

Since, it is a energy produced in order to indicate the direction of heat produced we will use negative sign.

Q = $-1.6\times 10^4 kJ$

Moles of propane burnt to produce Q energy =n

$n\times \Delta H_{rxn}=Q$

$n=\frac{Q}{\Delta H_{rxn}}=\frac{-1.6\times 10^4 kJ}{-2044 kJ/mol}=7.83 mol$

According to reaction , 1 mol of propane gives 3 moles of carbon dioxide. then 7.83 moles of will give:

$\frac{1}{3}\times 7.83 mol=23.49 mol$ carbon dioxide gas.

Mass of 23.49 moles of carbon dioxide gas:

23.49 mol × 44 g/mol =1,033.56 g

1,033.56 grams of carbon dioxide was emitted into the atmosphere.

8 0

3 years ago

CO_2 sublimes readily at 25°C. Which properties are usually associated with a compound that undergoes this kind of change?

antoniya [11.8K]

Explanation:

Sublimation is defined as a process in which solid state of a substance directly changes into vapor or gaseous state without undergoing liquid phase.

For example, naphthalene balls show sublimation at room temperature.

As this process does not cause any change in chemical composition of a substance. Hence, it is known as a physical process.

Similarly, when $CO_{2}$ sublimes readily at $25^{o}C$ . This shows change in physical state of carbon dioxide is taking place, i.e, from solid to gaseous phase.

Thus, we can conclude that when $CO_{2}$ sublimes readily at $25^{o}C$ then it means physical properties are usually associated with a compound that undergoes this kind of change.

4 0

3 years ago