<span>It is because air is a poor conductor of heat. Good luck ;)</span>
Given mass of tungsten, W = 415 g
Molar mass of tungsten, W = 183.85 g/mol
Calculating moles of tungsten from mass and molar mass:
The first reason to repeat experiments is simply to verify results. Different science disciplines have different criteria for determining what good results are. Biological assays, for example must be done in at least triplicate to generate acceptable data. Science is built on the assumption that published experimental protocols are repeatable.
2) The next reason to repeat experiments is to develop skills necessary to extend established methods and develop new experiments. “Practice make perfect” is true for the concert hall and the chemical laboratory.
3) Refining experimental observations is another reason to repeat. Maybe you did not follow the progress of the reaction like you should have.
4) Another reason to repeat experiments is to study and/or improve them in way. In the synthetic chemistry laboratory, for example, there is always a desire to improve the yield of a synthetic step. Will certain changes in the experimental conditions lead to a better yield? The only way to find out is to try it! The scientific method informs us that it is best to only make one change at a time.
5) The final reason to repeat an extraction, chromatographic or synthetic protocol is to produce more of your target substance. This is sometimes referred to scale-up.
Your answer is <span>D) The angle of light from the sun as it reflects off the moon and viewed from the Earth's surface because of the way the sun hits the moon one side has to light the other doesn't and when the moon rotates the sun hits another part of the moon.
If you need more help I would be glad to help!
</span>*~"AB84"~*
<span>7/13 moles because a mole is one gram times the molecular weight. </span>
