Answer is IRON OXIDE Iron oxide acts as a flux, in addition to being responsible for imparting colour to cement. If the temperature goes higher, then iron oxide reacts with aluminium and calcium and results in the formation of calcium aluminate ferrite.
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Which compound gives green to cement?
(c) : Coloured cement obtain when 5% of colouring pigments, iron oxide and below 1 % Chromium oxides are added for green colour.
Which is the colour of cement?
Normally, the colour of ordinary Portland Cement is greenish grey.
Which compound is used in cement?
The cement contains 35 to 40 percent lime, 40 to 50 percent alumina, up to 15 percent iron oxides, and preferably not more than about 6 percent silica. The principal cementing compound is calcium aluminate (CaO · Al 2 O 3 ).
Which oxide is responsible for giving colour to cement?
Deficiency of which of the following oxide causes reduction Free 150 Questions 150 Marks 90 Mins Explanation Functions of cement ingredients:
Lime: CaO – Controls strength and Soundness, Its deficiency reduces strength and setting time. Silica: silicon dioxide (SiO 2 ) is called as silica. it is present as 17-25% of cement. Sufficient quantity of silica should be present in cement as it imparts strength to the cement. Also, if it is present in high quantity, it makes cement low heat hence safeguard against chemical action and heat resistant. Alumina: Alumina is Aluminium oxide (Al 2 O 3 ). It imparts quick setting property to the cement. Clinkering temperature is lowered by the presence of the requisite quantity of alumina. Excess alumina weakens the cement. It also increases heat of hydration Iron oxide: (Fe 2 O 3 ), Iron oxide imparts colour to cement. At a very high temperature, it imparts into the chemical reaction with calcium and aluminium to form tricalcium alumino-ferrite. Tricalcium alumino-ferrite imparts hardness and strength to cement.
Approximate oxide composition limits of ordinary portland cement are as follows:
| Oxide | Percentage Content |
| CaO | 60 – 67 |
| Si0 2 | 17 – 25 |
| Al 2 O 3 | 03 – 08 |
| Fe 2 O 3 | 0.5 – 6.0 |
| MgO | 0.5 – 4.0 |
| Alkalies (K 2 O, Na 2 O) | 0.4 – 1.3 |
| SO 3 | 1.3 – 3.0 |
India’s #1 Learning Platform Start Complete Exam Preparation Daily Live MasterClasses Practice Question Bank Mock Tests & Quizzes Trusted by 3.4 Crore+ Students : Deficiency of which of the following oxide causes reduction
How do you add color to cement?
Project Instructions – When working with cement-based products, always wear eye protection and waterproof gloves. Step 1 Drill a small hole in the lid so it will fit tightly around a ¼ inch piece of candle or glue stick. Step 2 Insert the glue stick or wax candle stick into the hole in the lid of the bottle.
Tip: While both glue and wax candle sticks work, wax candles are easier to drill out than glue. Step 3 In a small container, mix the concrete coloring pigment with water, and then add to the concrete, according to the instructions on the bag. Tip: The more pigment you add, the more intense the color will be.
Step 4 Add a little more warm water than usual to the mix so it will pour easier into the bottle. Step 5 Once poured into bottle, vibrate or tap out as many bubbles as possible. Then place glue/candle stick into bottle and screw cap back on. Wipe away excess concrete and let cure for at least 18 hours.
How do you make Coloured cement?
Using Dyes To Color Concrete Crafts – You can use dyes to color concrete, such as food coloring or, The method for coloring concrete this way is to add the dye to the water before mixing it into the dry concrete mix. Adding a food coloring dye won’t make the concrete color as concentrated as it would with a fabric dye.
