Category: Chemistry Notes PPT

Ammonium phosphate is a salt that is made up of ammonia and phosphorus, and its chemical formula is (NH4)3PO4.  However, this is a very unstable salt and due to how unstable it is, it is not exactly a salt worth a lot of commercial value. It can be formed by combining phosphoric acid along with ammonia, or by adding a lot more ammonia with acid phosphate.

For it to be used commercially, it is mostly obtained from crystalline powders. 

The Formula of Ammonium Phosphate

The molecular formula for this salt is (NH4)3PO4 and it is also referred to as triammonium phosphate or diazonium hydrogen phosphate.

How is Ammonium Phosphate Formed?

When phosphoric acid H3PO4 reacts with ammonia NH3 (it needs to be anhydrous in nature), we get the following reaction: 

NH3 + H3PO4 → NH4H2PO4

On combining concentrated quantities of both the products, ammonium phosphate is amassed in the form of a crystallised powder. This powder is soluble in water and if the water is boiled, then the solution loses the ammonia in the form of gas. This then results in the formation of acid phosphate (NH4)(H2PO4).

Structure of Ammonium Phosphate

What are the Properties of Ammonium Phosphate?

Every salt or compound has a set of distinct physical and chemical properties which are used as basic determinants to differentiate it from other chemical compounds and salts.

Physical Properties: 

Since this is a salt of ammonia, the characteristic smell of ammonia will always be present. The crystallised powder is white in colour. The powder is also very easily soluble in water with a pH that ranges between 4-4.5. 

Chemical Properties: 

The salt is highly unstable due to the nature of the compounds that are combined to make this.

Even though triammonium salt has an unstable nature, diammonium phosphate still holds an important position within the fertilizer industry. That being said, all the phosphate acids are divided into three categories:

• Phosphoric acid and super phosphoric acid

• Normal superphosphate and triple superphosphate

• Ammonium phosphate in granular form

Ammonium phosphate can readily react with lead nitrate, which results in the formation of ammonium nitrate and lead phosphate.

4(NH4)3PO4 + 3Pb(NO3)4 → Pb3(PO4)4 + 12NH4NO3

Anhydrous ammonia, when it reacts with phosphoric acid, also results in the production of the ammonium phosphate.

NH3 + H3PO4 à NH4H2PO4

Ammonium Phosphate Uses

Down below is a list of some of the major use cases of ammonium phosphate:

• Ammonium phosphate is used as a leavening agent during the process of bakingIts interaction with heat, results in instant evaporation without leaving any residue of ammonia

• Due to the ability of rapidly dissolving and becoming soluble, ammonium phosphate works as an effective fertilizer. It has two crucial elements embedded in them, the ammonium and phosphate, both of which are highly beneficial to the plants

• It also works great as a plant revitalize

• Ammonium phosphate can also be used as a great ingredient for dry chemical extinguisher

Solved Questions

1. If a sample of Ammonium phosphate (NH4)3PO4 has 3.18 moles of hydrogen atom then what is the number of moles available for oxygen atoms within the solution?

i) 0.265

ii) 1.06 

iii) 0.795

iv) 3.18

Solution: As we know that the molar mass of (NH4)3PO4 is 149 grams.

Within the same, contains 12 g of HSo for 3.18 moles, i.e. 3.18 grams of H, the total number of moles of ammonium phosphate:

12149×3.18​=39.5gm (NH4)3PO4

We know that 149 grams of (NH4)3PO4 contains 64g of oxygen

So, for 39.5 grams of (NH4)3PO4 it will contain 

14964×39.5​g of oxygen =16.96 gm oxygen

So, 16.96 grams of oxygen is present

Converting it into moles, we get, 1616.96 = 1.06 moles of OSo, the right answer is option ii).

 

2. If 6 moles of H are present in a sample of (NH4)3PO4, what is the number of moles of oxygen atom? Answer the question without converting the moles into grams.

1)     6

2)     4

3)     2

4)     1

Solution: We know that in ammonium phosphate:

The total number of H atoms: 12

Total number of O atoms: 4

We know that the ratio of atoms and moles remains the same

So, 12/4 = 6/X

Or, X = 2

So, the total number of moles of oxygen is 2.

Anthocyanin Definition

Anthocyanins are also known as Anthocyanins. These are water-soluble pigments present in plants, especially in fruits and vegetables. The red, blue, purple, pigments in fruits, vegetables and tubers are due to Anthocyanins. These pigments belonging to the phenol group are in glycosylated forms. When it comes to anthocyanin meaning, the word ‘Anthocyanins’ came from the combination of ‘Anthos’ and ‘Kyanous’. The former implies flowers whereas the latter signifies dark blue colour.   

Most of the red, blue, purple flowers contain Anthocyanins. For example, red hibiscus, red roses, pink blossom, blue rosemary, blue chicory, purple sage, purple mint, lavender are edible. Some of these are commonly used as food, colourants and as folk medicine too.

What Is Anthocyanin?

Anthocyanin is a sub-division of phenolic phytochemicals. It is mostly found in the fruits and flowers, particularly their epidermal tissues’ vacuolar sap. Since Anthocyanin is available as a glycoside, you can call it as a glycone. They are a subclass of flavonoids. Thus, they are polyphenols which give the unique colour of the plants or parts of the plants. Apart from normal anthocyanins, Acylated Anthocyanins are also present in plants.   

Properties of Anthocyanins

They are responsible for the red, blue or purple colours of vegetable petals, cereals like eggplants, onions, black rice, berries. Along with carotenoids, the autumn leaf colour is partially dependent on the presence of anthocyanins.

Based on their anthocyanin chemistry, they can be classified into two groups, flavonoids and phenolics. These plant pigments are soluble in water.

It has been used as an appetite stimulant, choleric agent and to prevent other diseases as well. Since this is a bioactive component, the bioavailability is the crucial factor for maintaining good health and healing several illnesses.

Source of Anthocyanins

The fruits, vegetables, grains containing anthocyanins are delicious as well as nutritious. Some of the foods that contain Anthocyanins in high amounts are blackberries, purple asparagus, concord grapes, pomegranates, eggplant, raspberries, purple corn, red cabbage, black rice. Still, Anthocyanins are present in fruits and vegetables; they are available in compound forms, not independently. And it is found that the effects are much better when they are consumed in combination with other compounds rather than in isolation. More research is still required to explore different aspects of Anthocyanins.

Uses of Anthocyanins

Anthocyanins have a vast area of applications.

• The red, blue or purple pigments extracted from the plants are widely used as dye or food colourant. For instance, Anthocyanin extracted from grape skin is heavily used for adding attractive colours to fruit jams, beverages, or confectionaries.

• Several anthocyanin-rich flowers and fruits are used as medicines for treating different ailments. They possess various properties like anti-microbial, anti-cancer, anti-inflammatory, anti-diabetic, as well as anti-obesity. They are also highly effective for the prevention of cardiovascular disease (CVDs). Hence Anthocyanins are potential pharmaceutical ingredients having great medicinal values.

• Since people are now concerned about the toxic effects of synthetic food pigment, the demand for plant-based colourants like Anthocyanins is increasing rapidly in the food industry.  

The Basic Anthocyanin Structure and Anthocyanin Formula

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This picture depicts the structure of anthocyanins. 

The structure of anthocyanin has come from flavylium ion and its basic formula is C15H11O+..  

Therapeutic Effects

Anthocyanins are known for their therapeutic effects in different diseases.

Anticancer: Anthocyanins have been studied extensively for treating cancer as well as antiangiogenesis. Antiangiogenesis is a method that stops new blood cell formation that sends oxygen to the tumour cells. It helps in developing cancerous cells. The study for particularly these diseases is based on models of animals along with in-vitro and cell structure. 

Anti-diabetic: Anthocyanins are widely used for treating diabetes as in many research, it is seen that anthocyanin-rich Cornus fruits work fantastic in diabetes treatment. For this reason, consumption of Cornus fruits has been prescribed in traditional diabetes treatment in China since ancient times. In studies, noticeable improvement has been seen due to the consumption of anthocyanin-rich fruits for eight weeks at one go.

Anti-obesity: Anthocyanins have potential to fight against obesity. According to a study, the inclusion of purple corn in a regular diet for 12 weeks helps to reduce body weight as well as the weight of white and brown adipose tissues also decreases.

Ion exchange is the reversible exchange of one type of ion on an insoluble solid with another of a similar charge present in a solution surrounding the solid.

It is accomplished through the use of a process for water softening or demineralization, chemical purification, and material separation.

Ion exchange is a term used to describe a method of purifying aqueous solutions utilising solid polymeric ion-exchange resin. More exactly, the phrase refers to a wide range of processes involving the exchange of ions between two electrolytes. 

The process is frequently used for the purification and separation of several industrially and medicinally significant compounds, in addition to drinking water purification. Although the phrase is most commonly associated with the use of synthetic (man-made) resins, it can also apply to a variety of different materials, such as soil.

Ion Exchange Process

A microporous exchange resin supersaturated with a loosely held solution is the main component of ion exchange equipment. Sulfonated polystyrene beds that have been supersaturated with sodium to cover the bed surface are commonly used for water softening. Ions attach to the resin beads as water travels through the resin bed, releasing the loosely contained solution into the water.

The exchange resin must be replenished or recharged after the beds get saturated. The salt brine solution flushes the ion exchange resin to revive it. The ions in the wastewater are exchanged with the sodium ions in the salt brine solution.

Uses

Water softening (removal of calcium and magnesium ions), water demineralization (removal of all ions), and de-alkalinization are the most prevalent uses of ion exchangers (removal of bicarbonates). 

Iron, lead, radium, barium and copper can all be removed from water using cation exchange resins. Nitrate, sulphate, and other negatively charged atoms can be removed by anionic exchange units (called anions). Researchers are working on resins that will allow them to extract nitrate more selectively than is currently possible. 

In the chemical sector, ion exchangers are also used to extract or recover metal ions from effluent. Due to the poor selectivity of the resins, some pollutants (such as arsenic, fluoride, and lithium ions) are difficult to remove using ion exchange.

Sweetening Agent

An artificial sweetener or a sweetening agent is a sugar substitute, known as a food additive, which provides you with a sweet taste similar to that of sugar. However, it contains significantly less food energy as compared to the sugar-based sweeteners, which makes it a zero-calorie or a low-calorie sweetener. Artificial sweeteners can be derived through different plant extracts or when they are processed by chemical synthesis. Artificial sweeteners are many times sweeter when compared to regular sugar and hence they are also sometimes known as intense sweeteners. 

Many of these artificial sweeteners are so sweet to an extent that either dextrose or maltodextrin is added to these sweeteners for reducing the intense sweetness. These sweetening agents, however, are usually obtained from synthetic sugar substitutes. They have also formed from natural substances such as herbs or just the sugar itself.

Artificial sweeteners are amongst the most attractive substitutes to sugar since they do not add too many calories in your diet. They can also be used directly in many of the processed food such as in dairy products, puddings, candy, baked goods, jams, soft drinks, and several other beverages and food items. They can also be used once they are mixed with starch-based sweeteners. Today, we will be learning about what artificial sweeteners are, the advantages and disadvantages of natural sweeteners, and look at the artificial sweeteners examples in this natural and artificial sweeteners PDF.

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How Do Artificial Sweeteners Work?

Let us learn how artificial sweeteners work in our body.

For the proper functioning of the sweetening agent, it must be soluble in water and should readily bind to the receptor molecule which is present on our tongue surface. The receptor is connected to a G- protein. Whenever the sweetening agent binds to the receptor, the G- protein starts to dissociate, which helps to activate a nearby enzyme. As a result, it tends to trigger a sequence of events wherein the signals get transmitted to and then are interpreted by our brain. This interaction between the sweetener and the receptor is responsible for the sweetness that the artificial sweetening agent has.

Advantages and Disadvantages of Natural Sweeteners

Natural sweeteners tend to have a huge variety of uses, be it at home, or in the processed foods. They are sometimes also referred to as added sugars since they are added to different food items during processing. Let us discuss the advantages and disadvantages of natural sweeteners.

Natural sugar substitutes can often turn out to be healthier than sugar. However, their vitamin and mineral content is not much different. Consider, for example, both honey and sugar are similar nutritionally. Your body would process both of these into glucose and fructose only. Hence, it is fine to consume a natural sweetener depending on how its taste is and not on its health claims. However, be sure to use any sorts of added sweetener sparingly.

Generally, natural sweeteners are safe. However, there is no health advantage for consuming any kind of added sugar. If you consume too much sugar, even if it is a natural sweetener, it could lead to many health issues like weight gain, poor nutrition, tooth decay, and increased levels of triglycerides. Also, you shouldn’t give honey to kids younger than 1 year of age.

Consuming sugars in moderation is always the key to lead a healthy life. When you choose your sugar substitutes, it tends to pay for being a savvy consumer. Artificial sweeteners can surely help in managing your weight. However, they are no magic bullet and you should consume them only at moderate levels.

While we learn about the behaviour of a compound or an atom, the size of the atoms plays an essential role. One of the ways in which we can express the size of an atom is with the help of atomic radius. It helps us in understanding why some of the molecules fit in together and the rest contain parts which get crowded under different conditions. The atomic size is defined by its orbital edge. However, these orbital boundaries are quite fuzzy and tend to vary in different conditions. For standardizing the measurement of the atomic radius, the distance between the nuclei of two similar atoms that are bonded together is measured. We can, therefore, define the atomic radius of elements as half of the distance between the nuclei of similar atoms which are bonded together. 

Today, we will learn about what is atomic radius periodic table, the atomic radius definition, what is the atomic radius trend, what is atomic size periodic table, and the atomic size trend.

Atomic Radius Definition

Let us now define the atomic radius.

The atomic radius of an element refers to the measure of the size of the element’s atoms, which is typically the mean distance from the nucleus centre to the boundary of its surrounding shells of the electrons. However, since the boundary is not well-defined, there are several non-equivalent definitions of the atomic radius. There are three types of atomic radii which are Van der Waals radius, covalent radius and ionic radius.

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Measurement of Atomic Radius

Let us learn how the atomic radius is measured and what is its unit.

Atomic radii are measured for elements. The units for measuring the atomic radii are picometers, which is equal to 10−12 meters. Consider, for, example, the internuclear distance between two hydrogen atoms in the H2 molecule is known to be 74 pm. Hence, the atomic radius of the hydrogen atom is 74/2 = 37  pm

Atomic Size Trend

Let us learn about what is the trend in atomic radii down a group.

When we move down the group or across the row or column in the periodic table, we would observe a lot many trends in the elements, both physical and chemical. Consider, for example, while moving down the group of the non-metals, the reactivity of the elements tends to decrease, whereas, it tends to increase when we move down the group of the representative metals.

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When we combine two atoms, we can then estimate their atomic size when we check the distance between the two atoms. The other method through which we can measure the atomic size of a given non-metallic element is by the formation of a single covalent bond between the two atoms and then check the distance between the two atoms. The radius which is found by this method is called the covalent radii of the element. However, in the case of a metal, it is known as a metallic radius. It is defined as one half of the distance between the nuclei of the two adjoining metal ions that are joined by a metallic bond.

The atomic radius of an atom is measured with the help of X-ray or several other spectroscopy methods. The atomic radii of the elements tend to vary in the periodic table but a fixed manner. We can explain this trend when we consider the nuclear charge and the energy level.

Typically, the atomic radius tends to decrease as we move from the left to right in a period and it tends to increase when we move downwards in a group. The reason being that in periods, the valence electrons tend to lie in the same outermost shell. The atomic number tends to increase within the same period when we move from the left towards the right which tends to increase the overall effective nuclear charge. The increase in the attractive forces, in turn, reduces the atomic radius of the elements.

You know that the force of attraction between the protons and electrons tend to play a very important role in the increasing or decreasing pattern of the atomic radius.

What is Barium Carbonate?

White in colour, Barium Carbonate is a solid element that precipitates from a solution of barium hydroxide and Urea. It has a chemical formula stated as BaCO3. Barium Carbonate is generally toxic in nature and comes in other forms like a mineral form called witherite and it can also be prepared from barytes with the help of precipitation. It can also be seen in glazes of turquoise. It is advisable to take proper protective measures while handling this chemical compound as it’s high toxicity is something that you shouldn’t be messing with. It should be strictly kept under low quality, preferably below 20%. It is also known as Barium Monocarbonate

The Barium Carbonate Formula is BaCO3

Physical Properties of Barium Carbonate – BaCO3

The above-mentioned table sums up the physical properties of Barium Carbonate.

BaCO3/ Barium Carbonate Structure

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Chemical Properties of Barium Carbonate – BaCO3

BaCO3 + CaSO4 → CaCO3 + BaSO4

• Barium Carbonate can react with Hydrochloric Acid to form Barium Chloride, Water, and Carbon Dioxide.

BaCO3 + 2HCl → BaCl2 + H20 + CO2

Various Uses of Barium Carbonate – BaCO₃

• Being a white insoluble salt that finds its largest usage in the Ceramics Industry, Barium Carbonate is widely used to make ceramic products.

• It also finds usage as a raw material for Barium oxide (BaO) and Barium peroxide (BaO2)

• Barium Carbonate is widely used as a rodenticide although its whitish flour-like appearance has resulted in many barium poisoning cases.

• Some of the major commercial applications of barium carbonate / BaCO3 includes glass, oil-drilling, photographic, ceramic, enamel, barium magnetic materials, paint, brick, and chemical industries. 

• Barium Carbonate is also used for the manufacturing of electronic ceramics, capacitors, PTC thermistors, and other types of electronic equipment.

• It is an important raw material for the production of magnetic components and fibre optical glass.

Production Method of BaCO3

1. Carbonation Method

The process of production of BaCO3 with the carbonation process involves the following:

• First carbon dioxide is passed through a solution of barium sulfide so that it can carbonize,

• The barium carbonate slurry obtained from this process is then further subjected to desulphurization wash

• It is then passed through vacuum filtration, and then dried at 300℃ 

• The final process involves pulverization before barium carbonate products can be obtained.

The Chemical Reaction

BaS + CO2 + H2O → BaCO3↓+ H2S↑

2. Metathesis Method

In the Metathesis method, barium sulfide and ammonium carbonate undertake a metathesis reaction resulting in barium carbonate. The end product is then washed, filtered, and dried in order to obtain bismuth products. 

The Chemical Reaction

BaS + (NH4) 2CO3 → BaCO3 ↓ + (NH4) 2S

3. Poison Nepheline Conversion Method

In this process, soluble barium salt is obtained by reacting witherite with an ammonium salt. The resultant ammonium carbonate is recycled to be used again. This ammonium carbonate is then added into the soluble barium slat obtained earlier to precipitate barium carbonate in refined form. The resultant BaCO3 is then filtered and dried to make barium carbonate based products. 

The Chemical Reaction

BaCl2 + NH4HCO3 + NH4OH → BaCO3 ↓ + 2NH4Cl + H2O

4. Dry Granulation Method

The process goes as follows:

Barium carbonate obtained from heavy precipitation is sieved and placed within the warehouse of raw materials. It is then stirred well, mixed, and then degassed. The material is then made to go t
hrough the rotary feeder. The end product is compressed with rollers into tablets in a thickness of 3.7 to 4 mm. The resultant tablets are then rolled into a sheet in the input granulator and its speed is adjusted accordingly. This gives semi-finished products of barium.

The semi-finished products are subjected to the knife pulse pneumatic conveying method, which the products input into the vibration feeder to sieve. The granulator releases barium carbonate in particles larger than 20 mesh.

5. Wet Granulation Method

This method uses a precipitation system to filter a cake containing barium rich water in the process of manufacturing. The filter cake should have the capability to control the water content at about 20%. The material is then passed through the action of rotating blades and the material is rapidly mixed. It is then kneaded and mediated to form semi-dense particles/ wet pellets. The wet pellets are then put into the rotary kiln’s direct fire and then sintered at 800-1200℃. Then is it furthered screened, processed through iron removal, weighed, and then packed in particles of barium carbonate.

Interesting Fact:

Barium Carbonate or BaCO3 is also called Whiterite named after William Withering who discovered this white mineral in 1784 from barytes. It generally occurs in the veins of lead ores and is found naturally in a few places.