Answer:
Explanation:Although the term is quite new, our connection to nature is not. We depend on nature for our survival - without healthy ecosystems, our drinking water isn’t clean nor is the air we breathe. We also enjoy nature... studies show that people who spend time in nature tend to be happier than those that don’t. It can even act as a natural anti-depressant. With industry and urban sprawl expanding at unprecedented rates, Ecosystem Services attempt to translate the benefits we receive from nature into economic terms so we can better understand the trade-offs we are making between nature and industrial development.
I believe that it is a chemical change.
Explanation:
1 sugar solution =Distillation
2 Iron powder and sand=magnetic separation
3 petrol and diesel= Fractional distillation
4 Camphor and glass powder = Sublimation
Answer:
Wide melting point range - impure sample with multiple compounds
Experimental melting point is close to literature value - pure sample of a single compound
Experimental melting point is below literature value - impure sample with multiple compounds
Narrow melting point range - pure sample of a single compound
Explanation:
The melting point of substances are easily obtainable from literature such as the CRC Handbook of Physics and Chemistry.
A single pure substance is always observed to melt within a narrow temperature range. This melting temperature is always very close to the melting point recorded in literature for the pure compound.
However, an impure sample with multiple compounds will melt over a wide temperature range. We also have to recall that impurities lower the melting point of a pure substance. Hence, the experimental melting point of an impure sample with multiple compounds is always below the literature value.