What is the ph of citric acid


Citric acid is a weak acid often found in citrus fruits. It can be used as an acidic food additive in foods and beverages, as well as an ingredient in various health, hygiene and cosmetic products. The acidity of citric acid is measured on the pH scale and the pH of citric acid can vary depending on its concentration.

The pH of citric acid can typically range from 2 – 3 at full concentration, but the exact pH level depends on several factors, including the type and amount of other components present in the solution. A solution with higher concentrations of citric acid will have a lower pH than one with lower concentrations. The pH level also changes when additional substances are added to the solution such as water or other acids or bases like sodium hydroxide (NaOH) or potassium hydroxide (KOH).

  • When mixed with water only, pure citric acid has a pH between 2 – 3; however, when mixed with mineral salts like calcium chloride it has a pH value between 4-5 and when mixed with sodium hydroxide it has a pH value between 5 – 6.
  • Citric Acid can also be used to adjust the tartness of food products, where it’s typically used to balance flavors while retaining its acidic characteristics by adding either NaOH or KOH to increase its total alkalinity.
  • In addition, Citric Acid is commonly used to preserve fruits and vegetables by adding it directly to them in order to increase their shelf life by giving off carbon dioxide gas which prevents molding and bacteria growth.

What is pH?

Before we can discuss the pH of citric acid, it is important to understand what pH is and how it is measured. pH stands for “potential hydrogen,” which is a measure of the amount of hydrogen ions present in a solution. On the pH scale, which ranges from 0 to 14, 7 is a neutral value – this refers to pure water with an equal number of hydrogen and hydroxide ions. Values less than 7 indicate levels of increased acidity, while anything above 7 suggests basic (alkaline) elements.

The concentration of hydrogen ions can influence various chemical reactions in substances and solutions, so it is helpful to know the exact pH level of a substance before proceeding with any kind of treatment or reaction. For example, citric acid has a number of applications across industries – food production and manufacturing being some key examples – thus it’s important to know its exact pH level before using it in these contexts.

Citric acid has an approximate pH level of 2.2-2.4; as such, this puts citric acid firmly within the acidic side range on the pH scale – slightly over vinegar’s average 2 level – making it an ideal additive for food items such as dressings, sauces and jellies that require acidic compounds to properly form or congeal. Interestingly enough, you can actually taste citric acid’s acidic character with concentrations over .6%, but some applications use up to 30%.

What is Citric Acid?

Citric acid is a weak organic acid most commonly found in citrus fruits, such as oranges and lemons. It is manufactured for use in the food and beverage industry, as well as for many non-food uses. The chemical formula for citric acid is C6H8O7, and it has a faint aroma similar to that of tart lemons.

The pH of citric acid is slightly acidic with a typical range of 2-3 on the pH scale. This means that pure citric acid can be used both to lower the pH of a mixture (acidifying) or raise the pH (alkalizing). In addition to its effect on pH, Citric Acid also provides benefits such as flavor enhancement and preservation due to its antimicrobial properties. At high concentrations, Citric Acid can be caustic so it should always be handled with proper protective gear if necessary.

In food products, Citric Acid is classified by the FDA as “generally recognized as safe” (GRAS). Many beverages rely heavily on Citric Acid and you may see it listed on ingredient labels in dressings, jams & jellies and other products.

What is the pH of Citric Acid?

The pH of citric acid is variable and dependent on its concentration. Pure citric acid is a strong organic acid with a pKa of 3.13, meaning that it has the potential to be strongly basic and reactive in neutral, acidic or alkaline solutions. Citric acid can dissociate into hydrogen ions (H+) and respond to pH changes in the environment. As concentration increases, citric acid ions react with solution molecules more readily and the overall hydrogen ion (H+) concentration increases as well, contributing to an acidic solution.

At concentrations around 0.0002 mol/L (or 20 ppms), the pH of citric acid averages around 3 which is considered mildly acidic on the pH scale from 1-14 – with 1 being extremely acidic and 14 being extremely alkaline. At higher concentrations, citric acid can produce a more pronounced low pH environment capable of creating significant chemical or biochemical changes to occur in solution – such as precipitating metals out of solution or causing enzymatic activity reductions at very high concentrations (>2M).

It is also noteworthy that citric acid plays an important role as an active ingredient in many common cleaning products because it is known to increase water hardness when mixed with compounds like sodium carbonate – making it even more difficult for dirt particles to adhere to surfaces due its chelating properties! This makes it ideal for removing limescale buildup in laundry detergents and dishwashing soaps.

Factors Affecting the pH of Citric Acid

The pH of citric acid is affected by a number of factors, including the presence of buffer ions such as alkaline metal salts, ions from other organic acids, and organic bases. Additionally, the addition of certain substances can influence the solubility or ionization of citric acid in solution. As such, it is important to consider all these influences when determining its true pH.

Optimal Conditions

Under optimal conditions – that is, in a purified solution with no buffer ions present – the pH of citric acid has been found to be between 2.2 and 2.4. This is due to the fact that most citric acid molecules exist in a neutral state at this range. In addition to its acidic properties, citric acid also functions as an antiseptic and flavoring agent in many food and beverage products due to its mild acidic nature.

Impact of Buffer Ions

The presence of alkaline metal salts, ions from other organic acids, or organic bases has the tendency to increase the ionization (or “buffering”) potential of citric acid solutions and reduce its overall acidic nature. When buffer ions are present, they react with free protons produced by dissociated water molecules to form a new compound – buffered hydrogen cations – resulting in increased basicity (higher pH). This phenomenon is commonly referred to as an “alkaline shift”. As such, it has been noted that solutions containing buffers tend to have higher pH values compared with pure ones without them present.

Solubility Effects

In certain cases where buffered solutions contain micelle-forming surfactants or amphiphilic components such as detergents or soap molecules for example; there may be an incidence of citric acid precipitation upon addition due to its low solubility under these conditions; this further contributes towards increased alkalinity (higher pH) because precipitated particles are not available for dissociation at different concentrations which can greatly reduce hydrogen ion availability in solution and raise the overall solution’s base number/pH value significantly.


The pH of citric acid can vary significantly depending on the concentration, pH of the solution, or where it comes from. Generally speaking, citric acid has a pH between 2-3 in its concentrated form with a pH around 4 in water solutions. At higher concentrations, it can have a pH as low as 1.

Citric acid’s large potential range makes it an important ingredient not just in food products but also cleaning and personal care items. Its mild acidity allows it to be used safely yet effectively in a range of products and applications.