Answer:Easter Islanders Didn't Cause Ecological Disaster on Their Island, New Research Finds. New research provides evidence contrary to the widely-held belief that the prehistoric population of Easter Island (Rapa Nui) caused an ecological disaster through rapid deforestation and over-exploitation of natural resources.
Answer:- The substance is Propane and right choice is C.
Solution:- 10140000 J of heat is used to boil 28.47 kg at 298 K. Here, the important thing is, the liquid is changing to vapor and the temperature is not changing means it's a phase change. So, the formula used for this is:
![q=m*\Delta H_v_a_p](https://tex.z-dn.net/?f=q%3Dm%2A%5CDelta%20H_v_a_p)
where, q is the heat energy, m is mass and
is the enthalpy of vaporization.
Let's rearrange the formula for
as:
= ![\frac{q}{m}](https://tex.z-dn.net/?f=%5Cfrac%7Bq%7D%7Bm%7D)
Let's plug in the values:
= ![\frac{10140000J}{28.47kg}](https://tex.z-dn.net/?f=%5Cfrac%7B10140000J%7D%7B28.47kg%7D)
= ![356164\frac{J}{kg}](https://tex.z-dn.net/?f=356164%5Cfrac%7BJ%7D%7Bkg%7D)
If we round this then it is
. Hence, the right choice is C. propane.
Answer:
1,39 L
Explanation:
Charle's Law states that the volume of a fixed amount of gas <em>maintained at constant pressure</em> is directly proportional to the<u> absolute temperature</u> of the gas, for a constant amount of gas we can write:
![\frac{V1}{T1}=\frac{V2}{T2}](https://tex.z-dn.net/?f=%5Cfrac%7BV1%7D%7BT1%7D%3D%5Cfrac%7BV2%7D%7BT2%7D)
As the pressure of the balloon doesn't change, we can use Charle's Law to solve the problem. Firs we change the given temperatures to absolute temperature units ( °K), using the following relations:
°K=273+°C
°K=5/9(°F-32)+273
Therefore:
V1=1.5 L, T1=273+25=298°K
V2=?, T2=5/9(36-32)+273=275,2°K
![V2=\frac{V1T2}{T1}=\frac{275,2*1,5}{298}=1,39L](https://tex.z-dn.net/?f=V2%3D%5Cfrac%7BV1T2%7D%7BT1%7D%3D%5Cfrac%7B275%2C2%2A1%2C5%7D%7B298%7D%3D1%2C39L)
The new volume of the balloon is 1,39 L.
Answer:
Metals are good conductors of heat. Due to this property metals are used in the preparation of kitchen utensils. Aluminium is good conductor of heat and more over it is corrosion resistent. Due to these properties aluminium is used in making kitchen utensils.
Explanation: