Why sandpaper a metal before experiment

The magnesium reacts with oxygen to produce the oxide. Students see there is an increase in mass and can use the results to find the formula of magnesium oxide. This experiment is included in our Conservation of mass video, along with supporting resources , including illustrated technician notes , integrated instructions , worksheets, a structure strip and more.

The practical activity takes around 30—45 minutes, depending on the competence of the class. Students should all be standing and should wear eye protection. Students with long hair should tie it back. It is a good idea for students to practice lifting the lid on and off the crucible and the crucible off the pipe clay triangle before they start.

This has the added bonus of checking that all the tongs are functioning correctly. To enable students to light their Bunsen burners they will need access to matches or lighters. The most significant hazard in this experiment is the hot apparatus. Warn students that it will take some time to cool down. For classes with shorter attention spans, the final step of heating to constant mass could be omitted. The apparatus and set up required to calculate the change on mass when magnesium burns.

Learn More. Search for products or advice No product results found for your search. Related Products. View More Products. Related Pages. View More Pages. Popular Products. Berger Everlast Range Advice and Products. Subtotal inc GST. Total inc GST. The only difference between sandpaper and larger tools is that sandpaper can't be sharpened.

When you push sandpaper across a piece of wood, the abrasive grains cut tiny shavings out of the surface. To the naked eye, these shavings look like dust, but magnified, they're just like the shavings produced by other cutting tools. These shavings are called swarf by people in the know.

Now, if you look closely, you'll see that on some types of sandpaper, there are spaces between the abrasive grains. This is called an open coat, and it gives the shavings--excuse me, the swarf--a place to go. This is especially important if you're sanding wood, where the swarf particles are larger than they are for glass or steel. To remove the Magnesium oxide layer from the ribbon which may prevent or slow down the burning of magnesium ribbon.

Unwanted impurities deposited on the magnesium ribbon can be removed and only pure magnesium can be used for the reaction.

Why do we rub magnesium ribbon with sandpaper before burning? Before burning in air, the magnesium ribbon is cleaned by rubbing with sandpaper. This is done to remove the protective layer of basic magnesium carbonate Mg CO3 2 from the surface of ribbon. Why magnesium ribbon is rubbed? Explanation: Magnesium is a highly reactive metal. When exposed to air it forms a layer of magnesium oxide on its surface, which prevents further reaction of magnesium with oxygen.

Magnesium ribbon is rubbed before burning because it has a coating of basic magnesium oxide. When magnesium ribbon is rubbed before burning because it has a coating of?

Magnesium ribbon is rubbed before burning because it has a coating of basic magnesium carbonate. Answer: Magnesium reacts with the atmospheric oxygen to form a layer of magnesium oxide due to which it loses its shiny surface. After rubbing with the sand paper, the oxide layer gets washed away and magnesium gets back its shiny surface and turns silver. Hint: Magnesium is a very reactive metal. When it is kept in the open air it can react with the gases present in the air.

Cleaning will remove those impurities formed due to the reaction with air. Hint: Magnesium ribbons burn in air to form magnesium oxide and. Both magnesium and oxygen combine together to form magnesium oxide which is a white powder. Corrosion is a type of combination reaction in which two or more elements or compounds combine to form a single compound.

When magnesium ribbon burns in oxygen, magnesium oxide is formed with the production of dazzling white light.