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How can plaster of paris have half molecule of water

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  1. actually there is no half molecule of water.it is actually shared by two atoms of CaSO4 so its equivalent form for 1 CaSO4 is 1/2 H2O.... In plaster of Paris twomolecules of CaSO4 share one molecule of water, we represent only onemolecule of CaSO4 for which we show the half molecule of water 2 (CaSO4.2H2O) -----> 2CaSO4.H20 + 3 H2O 226 view
  2. plaster of paris is written as caso41 2h2o how is it possible to have half water molecule attached to caso4 - Chemistry - TopperLearning.com | tfqnt7rr. Starting early can help you score better! Avail 25% off on study pack. Avail Offer
  3. It is not possible to have half a molecule of water. The formula CaSO 4.1/2 H 2 O over here actually means that two molecules of CaSO 4 share one molecule of water. The formula of plaster of Paris can also be written as 2CaSO 4. H 2 O

In plaster of paris two formula units of CaSO 4 share one molecule of water. In the formula it is written as half water molecule because in the formula we are showing only one unit of CaSO 4. Recommend (0) Comment (0 The chemical name of the plaster of Paris is calcium sulfate hemihydrate because half-molecule of water is attached with calcium sulphate. Why is plaster of Paris hard? The addition of common salt accelerates the rate of setting, while little borax or alum reduces it Why is plaster of Paris written as Caso4.1/2H2O ? How is it possible to have half a water molecule attached to Caso4 - 522419 The modified material is now calcium sulfate hemihydrate, Plaster of Paris, and has only ½ a molecule of water, 2CaSO4·2H2O + Heat→ 2CaSO4·½H2O + steam. Since it takes in energy as heat it is an endothermic reaction. So, when we buy Plaster of Paris, we are buying the hemihydrate of calcium sulfate

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  1. However, Plaster of Paris is a hemihydrate compound, which means it contains half molecule of water in its structure. It is formed when gypsum (CaSO4.2H2O) calcium sulfate dihydrate loses its crystallization water through calcination. (Walter Scarborough et al.,2012) CaSO4·2H2O + heat → CaSO4·0.5H2O + 1.5H2O (released as steam)
  2. (i) Why is Plaster of Paris written as CaSO4.12H,O ? How is it possible to have half a water molecule attached to CaSO4? (ii) Why is sodium hydrogen carbonate an essential ingredient in antacids ? (iii) When electricity is passed through an aqueous solution of sodium chloride, three products are obtained. Why is the process called chlor-alkali.
  3. Calcium sulphate with half a molecule of water per molecule of the salt (hemi-hydrate) is called plaster of paris (plaster of paris). It is prepared by heating gypsum (CaSO 4 . 2H 2 O) at 120°C in rotary kilns, where it gets partially dehydrated
  4. When the dry plaster of paris powder is mixed with water it reforms into gypsum. Depending upon the temperature gypsum converts to hemihydrate or anhydrous form. What is chemical formula of plaster of Paris? The chemical name of plaster of Paris is calcium sulphate hemihydrate because half molecule of water is attached with calcium sulphate
  5. The chemical name of plaster of Paris is calcium sulphate hemihydrate because half molecule of water is attached with calcium sulphate. The chemical formula of plaster of Paris is CaSO4. 1/2H2O
  6. eral composed of calcium sulfate dihydrate whereas Plaster of Paris is made by heating gypsum and then mixing the dry plaster powder with water

It is highly helpful in constructing statues and buildings, It can also be used as medicines and to repair broken bones. Calcium sulphate with half a molecule of water per molecule of the salt (hemi-hydrate) is called plaster of paris (plaster of paris). plaster of paris is prepared by heating gypsum (CaSO4. Is plaster of Paris harmful for health This product is known as the plaster of Paris. However, when water is mixed with dry plaster of Paris, it re-structures into gypsum. Why is plaster of Paris written as CaSO4 1 2h2o How is it possible to have half a molecule of water attached to CaSO4? Half a molecule of water means that two units of a chemical substance share one molecule of water It is highly helpful in constructing statues and buildings, It can also be used as medicines and to repair broken bones. Calcium sulphate with half a molecule of water per molecule of the salt (hemi-hydrate) is called plaster of paris (plaster of paris). plaster of paris is prepared by heating gypsum (CaSO4.12 Jan 2019 What [

How is it possible for plaster of Paris to have half a

Give reasons for the following : (i) Only one half of water molecule is shown in the formula of Plaster of Paris. (ii) Sodium hydrogen carbonate is used as an antacid. (iii) On strong heating, blue coloured copper sulphate crystals turn white

plaster of paris is written as caso41 2h2o how is it

When plaster of Paris reacted with water it get hydrated and as we know it is a derivative of gypsum so after reacting with water it gains it's half of the water molecule and form gypsum so that because it sets into hard mass. (caso4 + 1/2H2O=CaSO4.2H2O) plz marked as brainleis The formula CaSO₄.1/2 H₂O means that two formula units of CaSO₄ shares one molecule of water , in such a way that the effective water of crystallisation of one particular unit of calcium sulphate comes to 1/2 molecule of water. Plaster of Paris = 2CaSO₄.H₂O , OR, CaSO₄.1/2 H₂O Pranesh007 Pranesh00 Plaster of Paris when reacts with water liberating heat through crystallization. Gypsum is produced by heating plaster of paris to about 150-degree Celsius. When the dry plaster of paris powder is mixed with water it reforms into gypsum. Depending upon the temperature gypsum converts to hemihydrate or anhydrous form (a) Plaster of Paris is written as CaSO4.12H2O,because in this compound, 2 water molecules are attached to one calcium sulphate molecule. (b) Sodium hydrogen carbonate is a mild base. It neutralize acidic character but does not impart noticeable basic character. (c) When sodium chloride is electrolysed, sodium is obtained at cathode which then reacts with water to give alkali and hydrogen 1. In plaster of paris, two molecules of calcium sulphate share one molecule of water of hydration. Therefore, to write the formula, half a molecule of water is written. 2. The products formed when electricity is passed through an aqueous solution of sodium chloride, the products formed are chlorine gas, hydrogen gas and sodium hydroxide

Calcium sulphate with half a molecule of water per molecule of the salt (hemi-hydrate) is called plaster of paris (plaster of paris). plaster of paris is prepared by heating gypsum (CaSO4. Is plaster of Paris waterproof? Plaster of Paris is an extremely porous material when dried, and as such, will absorb any new water that touches its surface Half a molecule of water means that two units of a chemical substance share one molecule of water. In plaster of Paris, two units of calcium sulphate share one molecule of water, making it 1/2 molecule of water per CaSO 4 unit. This is why it is known as calcium sulphate hemihydrate and the chemical formula is CaSO 4.1/2H 2 O Plaster of Paris is generally used to support fractured bones in their correct positions. In, only half a water molecule is shown as the water of crystallization because two molecules of CaSO 4 share one molecule of water. Plaster of Paris is used for making toys, materials for decoration, and for making smooth surfaces Plaster of Paris is manufactured by heating gypsum at 423K or 150o C/300o F. On heating gypsum at 423 K, it loses water molecules and becomes calcium sulfate hemihydrate. This product is known as the plaster of Paris. However, when water is mixed with dry plaster of Paris, it re-structures into gypsum

why is one molecule of plaster of paris having a share of

Why is Plaster of Paris written as CaSO4

  1. Why is the formula of Plaster of Paris written as CaSO4.7H2O? How is it possible to have half of water molecule attached to CaSO4? Answer. Answer verified by Toppr . Upvote (0
  2. The gypsum gets converted to Plaster of Paris at 373 K. Gypsum is plaster of paris. when it is heated it will melt. Explanation: Gypsum is a compound known as calcium sulfate bihydrate and when it is heated to 373K, it looses its water of crystallization and forms a compound named calcium sulfate hemihydrate
  3. How can we get half a water molecule in plaster of Paris? It is not possible to have half molecule of water . The formula CaSO4.1/2 H2O means that two formula units of CaSO4 shares one molecule of water , in such a way that the effective water of crystallisation of one particular unit of calcium sulphate comes to 1/2 molecule of water
  4. Que 12. Why is Plaster of Paris written as CaSO 4.½H 2 O? How is it possible to have half a water molecule attached to CuSO 4? Ans 12. The actual formula of Plaster of Paris is 2CaSO 4.H 2 O which means that one molecule of H 2 O is associated with two molecules of CaSO 4.The formula for simplicity is written as CaSO 4. ½H 2 O.. Que 13
  5. eral gypsum.It has many uses in industry. All forms are white solids that are poorly soluble in water
  6. Plaster of Paris (cast and hardened) is susceptible to humidity it is porous and breathes : when in environment with high humidity it will absorb part of it when conditions are dry it will give back the humidity. This cycle will not affect the qua..

What Is The Chemical Reaction Between Plaster Of Paris And

Why is plaster of Paris written as Caso4

Types Clay plaster. Clay plaster is a mixture of clay, sand and water with the addition of plant fibers for tensile strength over wood lath.. Clay plaster has been used since antiquity. Settlers in the American colonies used clay plaster on the interiors of their houses: Interior plastering in the form of clay antedated even the building of houses of frame, and must have been visible in the. Answer. The chemical name of plaster of Paris is calcium sulphate hemihydrate because half-molecule of water is attached with calcium sulphate. The chemical formula of plaster of Paris is C aS O4. . .1/2H 2O. Advantages: It is light in weight and more durable. It has low thermal conductivity ratio of water and plaster of paris for sculpture. It's been a long time since I've used any sort of scale but if I remember right it's 100 water 70 plaster. Not quite half and half. I'll give you my quick shortcut version. Pour water until it's about half the volume you want to end up with. Then sprinkle in plaster Generally, you'll want to use approximately a 1:1 ratio of plaster to water—in other words, half and half. How hard is plaster of Paris? Plaster of Paris is a very soft mineral although it can be relatively strong when it is used as a cast. On the Mohs scale of mineral hardness, with talc being 1 and diamond being 10, Plaster of Paris is a 2

Plaster of Paris - Gypsum: Plaster of Paris is de-hydrated gypsum. Gypsum is a naturally forming non-metallic mineral, found as a rock or sand composed of 70.1% calcium sulphate and 20.9% water by weight. Its chemical formula is CaSO 4 · 2H 2O As plaster sculptures can be cleaned, carved, and treated to look like stone, bronze, and other more costly materials, and plaster casts can be finished to look like china or earthenware, it is not surprising that plaster of Paris is often encountered in museum objects as a substitute for stone or ceramic We can prepare this compound by heating the gypsum which contains calcium sulfate dihydrate (CaSO 4 ·2H 2 O) to a temperature of about 150 o C (120-180 o C). we should add certain additives when heating. Plaster of Paris is a fine, white powder. When it becomes hydrated, we can use it to mould things, and if we allow it to dry, it hardens and retains whatever the shape it is set before drying In fact, however much plaster you think you might need you will have to start with somewhat more than half that amount of water, as the plaster you add will almost double the volume of the water. Using your hand, start adding the plaster to the water by sifting it through your fingers handful by handful

Plaster of Paris Mixing Guide - Observation

  1. utes before it begins to set. Carefully about half a cup into the mold. Turn the mold at an angle so the plaster can reach the fingers in the mold. Continue to fill the mold
  2. The chemical name of plaster of Paris is calcium sulphate hemihydratebecause half molecule of water is attached with calcium sulphate. The chemical formula of plaster of Paris is is CaSO4. 1/2H2O. In respect to this, when was plaster of Paris invented? Plaster was first made about 9000 years ago, and has been used by ancien
  3. plaster of paris: a heavy white powder that forms a thick paste that hardens quickly when mixed with water. Plaster of paris casts are heavier than fiberglass casts and don't hold up well in water. synthetic (fiberglass) material: made out of fiberglass, a kind of moldable plastic, these casts come in many bright colors and are lighter. The.
  4. In the formula of plaster of paris, given in the above equation, only half a water molecule is shown as the water of crystallisation. It is not possible to have half a molecule of water. This formula actually means that 1 water molecule is shared by 2 CaSO 4 molecules so that the effective water of crystallisation for one CaSO 4 unit comes to.
  5. (two molecules os calcium sulphate share a water molecule) This process is reversible, so if you mix plaster with water, it re-forms into gypsum, releasing heat. Plaster can occur naturally like the deposits at Montmartre in Paris, that is why it is commonly known as plaster of Paris

Essentially, plaster in its final form uses some of the water you mix with it to form a crystalline structure (gypsum). By heating it to 150C half of the water is driven off leaving just one water molecule for every two molecules of plaster. If you heat it too much, too much water will be driven off and the plaster will not act normally. Good luck About one billion tons of gypsum deposits are spread over many sites in Nigeria. Plaster of Paris which is calcium sulphate with half molecule of water of crystallization (CaSo4. ½ H2 o) and hygroscopic characteristics obtained by duly calcined the raw material i.e. Gypsum (CaSo42H2o) Cup 1 water Cup 2 water and plaster Cup 3 soapy water 2. Add water to half fill each of the three cups. 3. To the cup labeled water and plaster, add about ¼ teaspoon of plaster of paris powder. Stir until the plaster of paris powder is thoroughly mixed with the water. 4. Using a clean teaspoon, add three teaspoons of grated soap to the soapy water

Combine one part water with two parts plaster of Paris powder in a disposable bowl. Place the water in the bowl first, and then sift the plaster powder over the water surface slowly. Tap the sides of the bowl as you add the plaster so all the powder settles beneath the water surface POP - Plaster of Paris ; (CaSO4), H20 Plaster of Paris has a very remarkable property of setting into a hard mass on wetting with proper quantity of water 2(CaSO4)2, H20 +3 H20 ———- > 2(CaSO4,2H2O). Gypsum : ( CaSO4, 2H2O They can survive only in a narrow range of pH change.- Our body works at the pH range of 7.0 to 7.8.- When pH of rain water is less than 5.6, it is called acid rain. When it flows into rivers, it lowers the pH of river water. It adversely affects the survival of aquatic life. What is the pH of the soil in your backyard Plaster bonds well to old without heating the model. Just a paint brush dipped in water & brush the area where your going to slap/ pour the new stuff. If the old surface isn't super smooth / glossy you shouldn't have to rough it up but if you do 80 grit sandpaper would work. I have always added layers within a day or 2 of the old cast Gypsum Plaster. Dry Gypsum is mixed in water and then heated at high temperatures to arrive at this usable form of Plaster of Paris. Apart from using it as a craft material, it is also used to by great artists to carve sculptures. This type of Plaster of Paris can also be used over wood, stone and other metals to improve their appearances.

Gypsum Plastering (Plaster Of Paris)-A Detailed Revie

(i) Why is Plaster of Paris written asCaSO4

Plaster of Paris is a white powder and on mixing with water, it changes to gypsum once again giving a hard solid mass. CaSO 4.1/2H 2 O + 3/2 H 2 O ® CaSO 4.2H 2 O (Plaster of Paris) (Gypsum) Note that only half a water molecule is shown to be attached as water of crystallisation. How can you get half a water molecule The chemical name of plaster of Paris is calcium sulphate hemihydrate because half molecule of water is attached with calcium sulphate. The chemical formula of plaster of Paris is is CaSO4. 1/2H2O. Is mixing flour and water a reversible change? Mixing flour and water would be a physical change, since neither the water nor the flour are changing. Plaster of Paris is 2CaSO4.H2O. When we heat gypsum (CaSO4.2H2O) to about 120°C, it loses a molecule of water and forms the hemihydrate (2CaSO4.H2O) which is commonly called plaster of paris. Plaster of Paris is written as CaSO 4 . 1/2 H 2 For every half pint of water (8 fluid ounces) add six to seven ounces of plaster of paris. When mixing, add the plaster of paris slowly to the water and stir constantly. When all of the lumps have disappeared and the mixture is smooth and has a thick gravy consistency, the plaster is ready for pouring Plaster of Paris is obtained by heating gypsum. The chemical formula of plaster of Paris is CaSO4.1/2H2O. Plaster of Paris is a white powder and on mixing with water it changes to gypsum resulting in a hard solid mass. It is mainly used by doctors as a plaster for setting the fractured bones in the right position

How is it possible to have half a water molecule attached to C a S O 4 ? Medium. View solution. Plaster of Paris should be stored in moisture -proof container. Explain why. Easy. View solution. View more. Learn with content. Watch learning videos, swipe through stories, and browse through concepts ever, just as that stamp can have all the gum removed with too much water, so too the bond can be altered with too much water. This is the reason that the first coat of a two-coat plaster operation on a bonded sur-face must be at least 3/8 inch and be reasonably dry. If the plaster is not dry enough, the bonding agent may flood with water. If you have a budding paleontologist at home, make your own dinosaur dig with plaster of Paris. This project is inexpensive and simple to assemble, and you can put it together with easily-found household materials. Not only can the kids assist in making the kit, but once it is finished, it will keep their little hands busy for hours Chapter 47 Dental Materials. STUDY. PLAY. homogeneous. A material that is uniform in quality and consistent throughout is said to be ___. lathe. A ___ is a machine used for cutting or polishing dental appliances. gypsum. ___ is the mineral used in the formation of plaster of Paris and stone

Question: What Happens When Plaster Of Paris Is Mixed With

  1. Why is plaster of Paris written as CaSO4 1 2h2o? On heating gypsum at 373K, it loses water molecules and become calcium sulphate hemihydrate (CaSO4. 1/2H2O). This is called Plaster of Paris. 1/2H2O) because two formula units of CaSO4, share one molecule of water
  2. Plaster of Paris should be stored in a moisture-proof container. Explain why ? Give two important used of washing soda and baking soda. Answer the following : (i) Why is Plaster of Paris written as CaSO 4 ­.1/2 H 2 O ? How is it possible to have half a water molecule attached to CaSO 4
  3. utes, life out the sculpture and cast another
  4. The plaster of Paris recipe is easy to follow, and the plaster can be poured into molds of nearly any shape to create lasting sculptures. There are also different ways to make homemade plaster of Paris using materials found in the home, making this an easy and inexpensive project
  5. half that of traditional sanded plaster. The lighter weight makes the vermiculite plaster easier to carry, mix and apply. plasters can have an attractive decorative appearance. Plaster of Paris. If this de-hydrated gypsum powder is then mixed with water, this paste or slurry will set rock hard
  6. To Harden Plaster-of-Paris Ob jects.—Put in an iron kettle 2 pounds of a solution of caustic potash. Add in shavings 2 ounces of stearin and 2 ounces of castile soap, and boil for half an hour, stirring constantly. Add 1 ounce of pearlash dissolved in a lit tle soft water. Let the whole boil up, remove from the fire, and stir un til cold

However, as you presumably have a flat new floor, using plaster of Paris probably is an unnecessary step. Shimming should be minimal, and a high-quality caulk around the base of the toilet leaving. Plaster of Paris as a model material for brittle porous solids. Journal of materials science, 28 (12) (1993), pp. 3221-3227. View Record in Scopus Google Scholar. A.E. Charola, J. Pühringer, M. Steiger Gypsum. A review of its role in the deterioration of building materials

(ii) Write chemical equation for the reaction of A with water. (iii) List two types of reaction in which this reaction may be classified. 6. Give reasons for the following : (i) Only one half of water molecule is shown in the formula of Plaster of Paris. (ii) Sodium hydrogen carbonate is used as an antacid Plaster of Paris is what I have used to make the bark. Yes, there are other products out there that may do this better, but I have found that Plaster of Paris works just the same can be cheaper. Due to the nature of plaster you have to work fast on this step. The Plaster of Paris need to be mixed with water until it is gloopy but stiff (if you.

The smaller 1/2 ball can be removed out of the larger one in a couple of hours after being poured. Once the pieces have set for at least 24 hours (unless using a quick setting concrete you can remove from the molds by turning upside and the piece should slide right out. After making two half's you can mortar them together Plaster, a pasty composition (as of lime or gypsum, water, and sand) that hardens on drying and is used for coating walls, ceilings, and partitions. Plaster was used as a medium of artistic expression until the 19th century. Learn more about plaster in this article Hello everyone, I have a old furnace I made a while back which is lined with plaster of paris, and as you can guess that degrades away quite fast due to part of the mixture being water. I was wondering what alternatives there were to lining my furnace/foundry with to avoid loosing too much heat while heating up a crucible and melting aluminium

Next, apply plaster of Paris to the strips of paper towel and drape over the structure. If necessary, trim the ends around the opening of the bottle. Ridges and structural features can be added with plaster or by shaping the newspaper substructure. Plaster of Paris will harden in about half an hour (i) Only one half of water molecule is shown in the formula of Plaster of Paris. (ii) Sodium hydrogen carbonate is used as an antacid. (iii) On strong heating, blue coloured copper sulphate crystals turn white. (Marks 3) OR (i) Draw a labelled diagram to show the preparation of hydrogen chloride gas in laboratory If the plaster is dead, it will react one of two ways. It will set. snap-set -- set in your bucket before you can get it thoroughly mixed. or it will not set at all. Try a small batch by weight so as not to waste the plaster. - 1 lb. water, 1.5 lbs plaster - and see what happens. If it does not set - you Hello johan. i think you are telling me. the plaster is to soft and they are breaking to easy. there are different plasters and they all have different strengths. soft.medium.and.hard.you can look for a plaster and buy small samples of the soft and medium grades to test the quality.to see what is best .but the moulds will only be as good as the originals.some silicon rubber moulds have to be. Paris, the substance which doctors use as plaster for supporting fractured bones in the right position. Plaster of Paris is a white powder and on mixing with water, it changes to gypsum once again giving a hard solid mass. Note that only half a water molecule is shown to be attached as water of crystallisation. How can you get half a water.

Quick Answer: What Is The Reaction Of Plaster Of Paris

5. adding to the step 3 slurry at least one water insoluble bonding agent in an amount from 0.25 to 3.0 percent by weight of the plaster of Paris and selected from the class consisting of zein, a cold-water insoluble polyvinyl acetate polymer in the form of dispersed particles having a softening temperature between 200 and 260°F., vinyl. What change would be observed in lime water? Write balanced chemical equation when (i) gas was evolved (ii) gas was passed through lime water. 7. Answer the following questions - i. Why is the formula of Plaster of Paris written as CaSO4.½H2O? How is it possible to have half of water molecule attached to CaSO4? ii

Calcined gypsum is used in making tile, wallboard, lath, and various plasters. When gypsum is heated to about 120 °C (250 °F), it loses three-quarters of its water, becoming the hemihydrate CaSO 4 ∙ 1 / 2 H 2 O, plaster of paris. If mixed with water, plaster of paris can be molded into shapes before it hardens by recrystallizing to. The powder to water ratio for mixing dental plaster in the lab is: Mineral used in the formation of plaster of Paris and stone. Gypsum. Removal of water to become one-half part water to one part of calcium sulfate, forming the powder product of gypsum. Hemihydrate 2 Blow out the plaster dust. Using a medium-bristle brush, scrub the area with a solution of water and tri-sodium phosphate (TSP) or a non-phosphate detergent. 3 Cut short pieces of self-adhesive fiberglass mesh joint tape and cover the groove with them. 4 Dip a sponge in clean water and dampen the area of the repair Lightly moisten the area to be plastered with a damp sponge or cloth. This helps the wet plaster of Paris to adhere better. Fill up the opening or crack with plaster using a putty knife. Smooth it until it's flush with the rest of the wall surface. If the area to be repaired is more than ½ inch deep or wide, fill the hole half full of plaster 3. How to Make Plaster of Paris Rat Poison. Put on your disposable gloves. Combine 1 cup each of flour or cornmeal, sugar or powdered chocolate mix and plaster of Paris. Blend the mixture very well. The smell of the sugar or chocolate will attract the rats and they will eat the bait

When dissolved in water, it evolves a large amount of heat and forms compound 'B'. Identify A and B. Write chemical equation for the reaction of A with water. List two types of reaction in which this reaction may be classified. 16. Give reasons for the following : Only one half of water molecule is shown in the formula of Plaster of Paris Step 1 to 5 making plaster mold for ceramics. We will start by preparing the plaster mixture. So you should mix the plaster powder with clean water. The proportions of the dough will vary according to the type of work to be done but to mold in a mold, the plaster paste must be quite liquid. To make the dough you must pour water into a perfectly. Casts have been produced from these ever since the clever Guiseppe Fiorelli, Director of the Excavations in 1864, decided to try pouring plaster into these mysterious hollows. This technique has enabled detailed body casts to be made of these first-century AD Romans in their final hour and has even been used to investigate the type of plants.

Quick Answer: What Is The Chemical Reaction Between

Cooooookies is a game that challenged players to accept as many browser cookies as possible. The championship appears to be over (winner:welp, who won 100lbs of real cookies) but you can still. Yes, plaster can get too old and become 'dead'. Old time plasterers used 'dead' plaster to patch pin holes or bubble holes in their finished plaster. Don't ask me whyguess it just 'works'. As to the pie tins drying slowly, as you discovered, you altered the mix by adding water. Plaster is cheapjust throw out a bad mix