<span>Petroleum and biomass are burned in combustion reactions, which liberate energy stored in chemical bonds. This is chemical energy. In contrast, nuclear energy comes from the conversion of mass into energy when an nuclear reaction occurs. Geothermal energy comes directly from heat sources underground, with no chemical or nuclear reactions.</span>
Greetings!
<h3>To find the empirical formula you need the relative atomic mass of each element!</h3>
N = 14
H = 1
S = 32.1
<h3>You can simply change the percentages into full grams</h3>
N = 12.20
H = 6.06
S = 48.45
<h3>Then you use this to find the Number of moles = amount in grams / atomic mass</h3>
N = 12.20 ÷ 14 = 0.8714
H = 6.06 ÷ 1 = 6.06
S = 48.45 ÷ 32.1 = 1.541
<h3>Then divide each number of moles by the smallest value:</h3>
N = 0.8714 ÷ 0.8714 = 1
H = 6.06 ÷ 0.8714 = 6.9 ≈ 7
S = 1.541 ÷ 0.8714 = 1.76 ≈ 2
So that means that there are 1 Nitrogen, 7 hydrogen, and 2 sulfur. This means the empirical formula would be:
NH₇S₂
Hope this helps!
<span>The independent variable is the one that does not change depending on other variables - so here it would be the presence or the absence of caffeine - this is dependent on Tina's actions, but not on other variables in the experiment. The dependent variable is the heart rate - it is assumed to depend on the presence or absence of caffeine. A hypothesis could be that "Caffeine causes an increase of heart rate in earthworms" - and this hypothesis is what the experiment is testing.</span>
Correct Answer: option C:The pair which consist of molecules having the same geometry is CH2CCI2 and CH2CH2.
Reason:
Both of the above molecules contain double bonds. They are characterized by sp^2 hybridization. Also, they possess a trigonal planar geometry. In trigonal planar system, the molecule consist of three equally spaced sp^2 hybrid orbitals, which arranged at angle 120 degree.
