Q. If t1=Time at which water is first added to cement, t2=Time when needle fails to penetrate 5 mm to 7 mm from bottom of the mould, t3=Time when the needle makes an impression but the attachment fails to do so, then what is initial setting time?

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Q. If t1=Time at which water is first added to cement, t2=Time when needle fails to penetrate 5 mm to 7 mm from bottom of the mould, t3=Time when the needle makes an impression but the attachment fails to do so, then what is final setting time?

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Q. What is the capacity of a measuring cylinder?

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Q. Portland cement is composed of four major oxides (CaO, SiO₂, Al₂O₃, Fe₂O₃ ≥90%).

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Q. Insoluble Residue mainly comes from which compound?

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Q. Loss on Ignition (L.O.I.) is the loss in weight of cement after being heated to _____________

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Q. C₄AF is not a true compound.

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Q. On cooling below 1250°C, C₃S decomposes ____________

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Q. Gypsum reacts with ____________ to form calcium sulfo aluminates and calcium sulfo ferrite.

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Q. C₃S and C₂S require approximately the _____________ amount of water for hydration.

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