# How effectively does the index of hydrogen deficiency in carbohydrates used in potassium nitrate propellant affect enthalpy change and its performance?

**Authors:** Sebastian Grabowski  
**arXiv:** [2303.06294](https://arxiv.org/abs/2303.06294)  
**Date:** 2023-03-11  
**Summary page:** https://www.summarizepaper.com/en/paper/2303.06294v1/

## Key points

- The study investigates the relationship between IHD and enthalpy of combustion of sugar-based rocket propellants.
- Eight different carbohydrate sources were used as fuels in the propellant, combined with potassium nitrate as an oxidizer in a 35:65 ratio.
- The IHD of the sugars ranged from 0 (polyols) to 2 (disaccharides).
- Propellants were burned in a controlled setting and data from calorimeters was utilized to analyze the enthalpy of combustion of various mixtures later.
- Results support the hypothesis that IHD is associated with the enthalpy of combustion of sugar propellant, with polyol reactions showing the highest enthalpy change.
- Carbohydrates with higher molar mass and an IHD of 2 exhibit better performance than those with an IHD of 1.
- The investigation provides insight into energy conservation and bond breaking/forming during chemical reactions.
- There is always a corresponding conversion of one kind of energy into another when one substance is transformed into another; this typically involves heat emission or absorption but can also involve light or electrical energy.
- The study sheds light on characteristics specific to sugar-based rocket propellants and their performance based on carbohydrate properties such as IHD and molar mass.

## Summary

This study investigates the relationship between the index of hydrogen deficiency (IHD) and the enthalpy of combustion of sugar-based rocket propellants, as well as the performance of carbohydrates with similar IHD values. The experiment used eight different carbohydrate sources as fuels in the propellant, combined with potassium nitrate as an oxidizer in a 35:65 ratio. The IHD of the sugars ranged from 0 (polyols) to 2 (disaccharides). To obtain data on combustion that is practical in real-world settings, propellants were burned in a controlled setting and data from calorimeters was utilized to analyze the enthalpy of combustion of various mixtures later. The results support the hypothesis that IHD is associated with the enthalpy of combustion of sugar propellant, with polyol reactions showing the highest enthalpy change. Moreover, carbohydrates with a higher molar mass and an IHD of 2 exhibit better performance than those with an IHD of 1. This investigation also provides insight into energy conservation and bond breaking/forming during chemical reactions. It explains that there is always a corresponding conversion of one kind of energy into another when one substance is transformed into another; this typically involves heat emission or absorption but can also involve light or electrical energy. Overall, this study sheds light on characteristics specific to sugar-based rocket propellants and their performance based on carbohydrate properties such as IHD and molar mass.