0
Tailor's Chalk is made from magnesium silicate or Mg3Si4O10(OH)2. Blackboard/ Chalkboard Chalk is made from calcium sulfate or CaSO4. Both were previously made from chalk a form of limestone that is a soft, white, porous sedimentary rock composed of calcium carbonate or CaCO3.
Other Names for Tailor's Chalk: Sewing Chalk, Magnesium Silicate, Soapstone, Talc, Slate
Other Names for Chalkboard/Blackboard Chalk: Calcium Sulfate, Gypsum, Gypsum Plaster, Plaster of Paris, Drierite, Alabaster, Anhydrite, Desert Rose
* Tailor's Chalk is used to temporarily mark clothing for alterations.
* Chalkboard/Blackboard Chalk is used for writing and/or drawing on a chalkboard,
blackboard, slate, or enamel board.
* Tailor's Chalk and Blackboard/Chalkboard Chalk are interchangeable though the
method of cleanup varies if the before mentioned chalk is used for it's intended
purpose or another usage.
* Chalkboard/Blackboard Chalk made from calcium sulfate is dust free.
* Chalk Sticks are made from calcium sulfate (calcium & sulphur molecules chemically bound to water) aka gypsum in its dihydrate form (chemical compound containing 2 molecules of water around each CaSO4 group aka calcium sulfate hemihydrate
* Chalk Sticks are made through calcination. Calcination is a treatment process of removing water from a substance or compound in this case calcium sulfate by heating the calcium sulfate to a high temperature that is also below melting or fusing point causing a loss of 50% to 75% of the calcium sulfate's original moisture producing a powder. When water is then added to the powder it rehydrates and quickly hardens.
* Calcium Sulfate predominately comes from Gypsum or Anhydrite though it also occurs as a byproduct of several different chemical processes
* Gypsum or Anhydrite occurs in many locations worldwide as evaporites (a natural salt or mineral sediment deposit left after the evaporation of a body of water)
* Pastels are made from calcium sulfate mixed with clay, oils, & pigment
* Soapstone is a metamorphic rock made mostly of Talc aka Magnesium Silicate
* Soapstone aka slate is what blackboards were first made from though most modern chalkboards are made with steel treated with an enamel
* Chalkboards can be made any color; Blackboards refer to the original blackboards made from soapstone aka slate
* Modern chalkboards are made with tiling grout; one of the main ingredients in tiling grout is Magnesium Silicate same as original Blackboards and Tailor's Chalk
* In early American schools children used a slate aka soapstone pencil to write on personal slate aka soapstone boards. These slate aka soapstone pencils were a cylinder of the rock inside cedar
* Slate pencils were replaced by soft chalk aka calcium carbonate (CaCO3) later replaced by calcium sulfate aka gypsum (CaSO4·2H2O)
Still curious? Ask our experts.
Chat with our AI personalities
Professor
Jordan
Blake
Add your answer:
Earn +20 pts
Explain Why blackboards are not scratched by chalk but by the sand embedded in the chalk?
Chalk is mostly made of calcium carbonate, which is softer than the materials in blackboards. When the chalk rubs against the blackboard, it does not scratch it because of its softer nature. However, chalk often contains trace amounts of sand or other harder impurities that can cause scratching on the blackboard surface.
Who uses a blackboard and chalk?
I am pretty sure it's a teacher.
Is sidewalk chalk made out of the same things as blackboard chalk?
Yes, both sidewalk chalk and blackboard chalk are typically made of calcium sulfate. However, sidewalk chalk is often mixed with additional ingredients like pigments and binding agents to make it more durable for outdoor use.
What element is in blackboard chalk dust?
Chalk is comprised of calcium sulfate. Specifically, it comes in the form CaSO4.2H2O, which is the dihydrate often known as gypsum.
What is tailor's chalk?
Tailor's chalk is a type of chalk that is designed to make temporary markings on cloth. Using this chalk, a tailor can mark where fabric needs to be cut or garments altered. Once the markings are no longer useful, they can be easily brushed off or washed out, leaving no residue behind.
