Answer:
Your answer is triglycerides. Hope this helps.
FeBr₃ ⇒ limiting reactant
mol NaBr = 1.428
<h3>Further explanation</h3>
Reaction
2FeBr₃ + 3Na₂S → Fe₂S₃ + 6NaBr
Limiting reactant⇒ smaller ratio (mol divide by coefficient reaction)
211 g of Iron (III) bromide(MW=295,56 g/mol), so mol FeBr₃ :

186 g of Sodium sulfide(MW=78,0452 g/mol), so mol Na₂S :

Coefficient ratio from the equation FeBr₃ : Na₂S = 2 : 3, so mol ratio :

So FeBr₃ as a limiting reactant(smaller ratio)
mol NaBr based on limiting reactant (FeBr₃) :

Wavelength= velocity/frequency
wavelength= (3.0 x 10^8m/s) / 7.5 x 10^12 Hz)
you can do the math
I am assuming u that 108 is 10^8 and the 1012 is 10^12
The number of calories that are required to change the temperature of 2.18 g of water from 15.3 c to 69.5 c is <u>118.16 cal</u>
<u><em> calculation</em></u>
- Heat in calories = MCΔ T where,
- M(mass)= 2.18 g
- C(specific heat capacity)= 1.00 cal/g/c
- ΔT( change in temperature)= 69.5- 15.3 =54.2 c
heat is therefore= 2.18 g x 1.00 cal/g/c x 54.2 c=118.16 cal