what is standard solution

What are standard solutions?

A standard solution is a a solution of accurately known concentration prepared from a primary standard (a compound which is stable, of high purity, highly soluble in water and of a high molar mass to allow for accurate weighing) that is weighed accurately and made up to a fixed volume.

What is standard solution example?

The most common include: Sodium chloride (NaCl), which is used as a primary standard for silver nitrate (AgNO₃) reactions. Zinc powder, which can be used to standardize EDTA (ethylenediaminetetraacetic acid) solutions after it has been dissolved in hydrochloric or sulfuric acid.

What is standard solution formula?

A standard solution can be prepared by dissolving a primary standard in a suitable solvent (such as distilled water). A primary standard is a soluble solid compound that is very pure, with a consistent formula that does not change on exposure to the atmosphere, and has a relatively high molar mass.

What is a standard solution Class 11?

What is a standard solution? A solution of known concentration is called the standard solution. A standard solution can be prepared by dissolving a known quantity of the substance in a definite volume of the solvent. The substance used to prepare the standard solution can be classified into two types.

Is NaOH a standard solution?

NaOH has no criteria given above. It is not suitable for the primary standards because they absorb the moisture from the atmosphere. It also absorbs carbon dioxide from the atmosphere. Hence, NaOH is not a primary standard because it has no quality of primary standard.

What are the functions of standard solution?

Standard solutions are solutions with a known concentration of a substance. They’re used in chemistry, particularly analytical chemistry, to help identify or determine the concentration of unknown substances.

What is the use of phenolphthalein?

Phenolphthalein is often used as an indicator in acid–base titrations. For this application, it turns colorless in acidic solutions and pink in basic solutions. It belongs to the class of dyes known as phthalein dyes.

What is the difference between primary and standard solution?

The key difference between primary and secondary standard solution is that primary standard solution has a high purity and less reactivity whereas secondary solution has a less purity and high reactivity. … Standard solutions have accurately known concentrations and we prepare these solutions using standard substances.

Is kmno4 a secondary standard?

potassium dichromate is primary standard as it is highly soluble in aqueous medium and does dissociate in presence of sunlight.. whereas potassium permanganate is secondary standard as it gets precipitated and dissociated in presence of sunlight.

Why was phenolphthalein used in the experiment?

A strong acid- strong base titration is performed using a phenolphthalein indicator. Phenolphtalein is chosen because it changes color in a pH range between 8.3 – 10. It will appear pink in basic solutions and clear in acidic solutions.

What makes a solution a standard solution?

D. A standard solution is any chemical solution which has a precisely known concentration. Similarly, a solution of known concentration has been standardized. To prepare a standard solution, a known mass of solute is dissolved and the solution is diluted to a precise volume.

How do you find the standard solution?

To make a standard solution, we have to calculate the number of moles of solute required and then calculate the corresponding mass. This is dissolved in a small volume of water and transferred to a standard or volumetric flask.

What is a standard solution in chemistry class 12?

Standard solutions are solutions that have a defined and correct quantity of the material or product (i.e. concentration). These solutions are often used to help identify and determine the concentration of an unknown substance.

What is the standard solution math?

Standard solutions are solutions that contain a known and accurate amount (i.e. concentration) of a substance or element. These solutions are commonly used in quantitative analysis to help identify and determine the concentration of a substance whose concentration is unknown.

What is standard solution and its type?

Standard solutions are solutions of accurately known concentrations, prepared using standard substances. There are two types of standard solutions known as primary solution and secondary solution. A primary standard solution is a solution with a high purity and less reactivity.

Is phenolphthalein a standard solution?

Phenolphthalein in basic solution. The standard solution is the solution in a titration whose concentration is known. … The end point of a titration is the point at which the indicator changes color. When phenolphthalein is the indicator, the end point will be signified by a faint pink color.

Is Na2CO3 a primary standard?

Only those acids or bases areconsidered primary standard which are stable and hence their strength do not change with time. Strength ofNa2CO3 also do not change hence it isconsidered as a primary standard. Na2CO3 is used as primary standardbecause it’s solution’s molarity remains constant for a very long period.

Is KMnO4 a primary standard solution?

KMnO4 is not used as primary standard because it is difficult to obtain the pure state of KMnO4 as it is not free from MnO2. Also, the colour is so intense that it acts as its own indicator.

What is titration used for?

Titration, also known as titrimetry, is a common laboratory method of quantitative chemical analysis that is used to determine the unknown concentration of an identified analyte (Medwick and Kirschner, 2010). Since volume measurements play a key role in titration, it is also known as volumetric analysis.

What chemical is used in titration?

Phenolphthalein, a commonly used indicator in acid and base titration.

What are the types of titration?

Types of Titration

Acid-base Titrations.
Redox Titrations.
Precipitation Titrations.
Complexometric Titrations.

What does pH stand for?

potential hydrogen pH, explained

pH may look like it belongs on the periodic table of elements, but it’s actually a unit of measurement. The abbreviation pH stands for potential hydrogen, and it tells us how much hydrogen is in liquids—and how active the hydrogen ion is.

What is the pH range of phenolphthalein?

Indicator Range

Indicator	Colour	pH range
Bromothymol Blue	yellow	6.0 – 7.6
Phenol Red	yellow	6.8 – 8.4
Thymol Blue – 2nd change	yellow	8.0 – 9.6
Phenolphthalein	colourless	8.2 – 10.0

Why is methyl orange used?

Methyl orange is a pH indicator frequently used in titration because of its clear and distinct color variance at different pH values. Methyl orange shows red color in acidic medium and yellow color in basic medium. Because it changes color at the pK_a of a mid strength acid, it is usually used in titration for acids.

Is HCl a primary standard?

HCl cannot be considered to be a primary standard because of its gaseous form at room temperature, but its solutions may be standardized against anhydrous Na₂CO₃. 4-5. … Explain how to prepare 250.00 mL of 0.0100 N Na₂B₄O₇10H₂O solution.

What is difference between primary and secondary solutions?

Primary standard solutions are solutions made out of primary standard substances. … A secondary standard solution is a solution that is made specifically for a certain analysis. A secondary standard is a substance whose active agent contents have been found by comparison against a primary standard.

Is HCl a primary or secondary standard?

Hydrochloric acid (HCl) solutions as a secondary standard

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A HCl solution is used as it can be prepared accurately and is quite stable. Because of this stability it is called a secondary standard. Even more accurate and stable standards are called primary standards.

Is feso4 a primary standard?

It cannot be a primary standard. Because it is not stable.

Is EDTA a primary standard?

EDTA always complexes metals with 1:1 stoichiometry. Unfortunately EDTA cannot be easily used as a primary standard. The H4Y form can be dried at 140◦C for 2 hrs and used as a primary standard, but is only sparingly soluble in water.

Is k2cr2o7 primary standard?

Potassium dichromate is a weaker oxidizing agent than KMnO₄ or Ce(IV). However, it is a primary standard and its solutions have long lasting stability in acid and are stable to light, to most organic matter, and to chloride ion. If needed, a K₂Cr₂O₇ solution can be standardized against pure iron. …

What is end point in titration?

end point: the point during a titration when an indicator shows that the amount of reactant necessary for a complete reaction has been added to a solution.

What is the pH range for methyl orange?

3.1-4.4

Indicator	pH Range	Acid
22 Methyl orange	3.1-4.4	red
23 Methyl red	4.4-6.3	red
16 Methyl violet	0.15-3.2	yellow
17 Methyl yellow	2.9-4.0	red

Why is a white tile used in titration?

For acid-alkali titrations, this is a chemical that undergoes a colour change at certain acidities. … A white tile can be placed underneath the conical flask to aid with the ease of spotting the end point colour change.

What does standardization mean in chemistry?

Standardization is the process of determining the exact concentration (molarity) of a solution. Titration is one type of analytical procedure often used in standardization. In a titration, an exact volume of one substance is reacted with a known amount of another substance.