Difference Between Benzoic Acid and Sodium Benzoate

Thekey differencebetween benzoic acid and sodium benzoate is thatbenzoic acid is the simplest aromaticcarboxylic acidwhereas sodium benzoate is the sodium salt of benzoic acid.

Benzoic acid is an aromatic carboxylic acid and sodium benzoate is a derivative of this benzoic acid. Both these are organic compounds because both these compounds have the aromatic苯ring, substituted with acarbonylgroup.

CONTENTS

1.Overview and Key Difference
2.什么是苯甲酸
3.What is Sodium Benzoate
4.并排比较 - 苯甲酸与苯甲酸钠的表格形式
5.概括

什么是苯甲酸

Benzoic acid is the simplest aromatic carboxylic acid. The molecular formula of benzoic acid is C₆H₅COOH. The molar mass of benzoic acid is about 122.12 g/mol. One benzoic acid molecule is composed of a benzene ring substituted with a carboxylic acid group (-COOH).

At room temperature and pressure, benzoic acid is a white crystalline solid. It is slightly soluble in water. Benzoic acid has a pleasant odour. The melting point of benzoic acid solid is about 122.41 °C. The boiling point of benzoic acid is given as 249.2 °C, but at 370 °C, it decomposes.

Benzoic acid can undergo electrophilic aromatic substitution due to the electron-withdrawing property of the carboxylic group. Carboxylic acid can provide the aromatic ring with pi electrons. Then it becomes rich in electrons. Therefore, electrophiles can react with the aromatic ring.

Benzoic acid is a fungistatic compound that is widely used as a food preservative. This means it can prevent fungi growth in food. Benzoic acid can be naturally found in some fruits such as berries.

What is Sodium Benzoate?

苯甲酸钠是具有化学式C6H5COONA的苯甲酸的钠盐。我们可以通过苯甲酸的中和反应产生它。这种生产方法涉及氢氧化钠和苯甲酸之间的反应。但是，在商业上，我们也可以通过氧的存在部分氧化来生产它。通常，苯甲酸钠与苯甲酸一起存在于许多食品中。一些丰富的资源包括蔬菜和水果。该化合物的主要应用是其用作食品防腐剂。

Sodium benzoate has the molar mass 144 g/mol. It appears as a white crystalline powder and it is odourless. The melting point of this compound is 410 °C.

What is the Difference Between Benzoic Acid and Sodium Benzoate?

苯甲酸和苯甲酸钠之间的关键区别在于苯甲酸是最简单的芳族羧酸，而苯甲酸钠是苯甲酸钠盐。However, both these are organic compounds because both these compounds have an aromatic benzene ring, substituted with a carbonyl group.

Moreover, benzoic acid is poorly water-soluble at room temperature, but if we heat the compound it becomes more water-soluble; however, sodium benzoate is water-soluble at room temperature. So, this is another difference between benzoic acid and sodium benzoate.

苯甲酸固体的熔点约为122.41°C。但是对于苯甲酸钠，熔点是非常高的值 - 410°C。此外，这两种化合物都以白色晶体固体形式出现，但是苯甲酸是针状结构，而苯甲酸钠通常是粉状固体。这两种化合物都作为食品防腐剂很重要。

概括– Benzoic Acid vs Sodium Benzoate

苯甲酸和苯甲酸钠之间的关键区别在于苯甲酸是最简单的芳族羧酸，而苯甲酸钠是苯甲酸钠盐。这两者都是有机化合物，因为这两种化合物均具有芳族苯环，用羰基取代。

Reference:

1. “Sodium Benzoate.” Wikipedia, Wikimedia Foundation, 3 Nov. 2019,Available here.
2. Helmenstine, Anne Marie. “How to Make a Benzoic Acid Snow Globe.” ThoughtCo, Jul. 5, 2018,Available here.

Image Courtesy:

1. “Pile of benzoic acid crystals” By Devon Fyson – Own work(CC BY-SA 4.0)viaCommons Wikimedia
2. “Sodium benzoate-substance” By Chemik10 at Polish Wikipedia(CC BY-SA 3.0)viaCommons Wikimedia