This is one change that affects iron articles and slowly destroys them. Since iron is used in making bridges, ships, cars, truck bodies and many other articles, the monetary loss due to rusting is huge.The process of rusting can be represented by the following equation:Iron (Fe) + Oxygen ( O2 , from the air) water …
This process of depositing a layer of zinc on iron is called galvanisation. The iron pipes we use in our homes to carry water are galvanised to prevent rusting.
Stainless steel is made by mixing iron with carbon and metals like chromium, nickel and manganese. It does not rust.
Some substances can be obtained in pure state from their solutions by crystallisation.
Physical changes are changes in the physical properties of substances. No new substances are formed in these changes. These changes may be reversible.
Rusting is the process in which of iron in the presence of moisture and air form a layer of a brownish substance called rust. Both air and moisture are necessary for rusting of iron objects. Due to the presence of the sea, In coastal areas, there is more moisture in the air. But, in the …
Explain why rusting of iron objects is faster in coastal areas than in deserts. Read More »
Take a water-filled beaker and add a few drops of dilute Sulphuric acid into it. Then the water is heated, when it starts boiling slowly add copper sulphate powder during this process stir continuously. Add more copper sulphate till no more powder can be dissolved. The solution is now filtered and allowed to cool down. …
Describe how crystal of copper sulphate are prepared Read More »
Chemical change is the burning of wood and cutting of wood is a physical change. The burning of wood produces ash and smoke that means two new substances are formed. Wood (cellulose ) changes into ash , carbon dioxide and water . Hence the properties of wood are changed. So, it’s a chemical change. When …
When some sour substance or curd ( lactobacillus bacteria ) is added to milk and kept long time, it turns into curd. Once the curd is formed, then there is no way curd can be converted back into milk. Both milk and curd are different and they have different properties So, the formation of curd …
How would you say that setting of curd is chemical change ? Read More »
The wax of the candle melts, then vaporizes and burns. Here Melting of wax is a physical change as no new substance is formed and the melted wax can be converted back to solid wax. When the wax burns, two new substances are formed which are water and carbon dioxide. So, it’s a chemical change. …
