Homework: Week
beginning 23rd March
This homework is all due by Friday 27Th
March
Spellings-
see homework sheet
Mathletics -
Please let us know if your child
cannot access Mathletics. Next week we will be revising angles, measurement and
time.
Literacy
Write a balanced argument: ‘should school holidays be made longer?’
Remember to include an
introduction, an argument for and against with reasons and evidence,
connectives and a conclusion.
Topic
Next week we will be building and designing our own Viking ships.
Please research the different types of Viking ships and designs in preparation
for our D.T lesson. Make some sketches and label what types of materials you will
need to collect over the week.
Science-on the blog
Please post advice for the school on the blog
explaining how rusting occurs, how it can be can be prevented and why it is
irreversible.
Rusting occurs when for example an iron nail is half in water and half out. Usually, rusting occurs naturally and this happens whaen something made from iron gets wet from the rain.
ReplyDeleteRusting can be prevented if you coat it with a substance for example, paint, oil, varnish or petroleum jelly.
Rusting is irreversible because it cannot be changed back to it's original state.
ReplyDeleteRusting is a process that occurs when a material ( e.g iron or steel ) comes into contact with oxygen and water.
Most of the time, the previously mentioned materials rust faster in acid rain or salt water. Aluminium, on the other hand, does not corrode easily, because its surface is protected by a layer of aluminium oxide. If the nail is fully submerged in water it is not as likely to rust as a half submerged one. The reason for this is that three things are needed to cause rust: water, oxygen and a certain material like iron.
The chemical equation for iron oxide is Fe203.
Rust can be prevented through covering in plastic coating, paint, or bringing into contact with magnesium. The last is done by the magnesium reacting before the iron or steel does and was often used on ships. However, it became inefficient due to the fact that it had to be replaced every once in a while.
Rusting may be prevented by:
1. Coating the surface (by painting for example) to prevent contact with the air.
2. Sacrificial protection of a more reactive metal.
Rusting occurs when oxygen combines into a metal which is named ‘Iron oxide’ which gives the metal a brownie type of color which is named ‘Rust.’ Rust can be formed also by putting metal half way in salt water or orange juice. The liquid and the ‘Iron Oxide’ form together which creates an even bigger substance of rust.
ReplyDeleteRust is an irreversible change because once rust has formed, you can’t get the rust off using the same materials.
However, using something like varnish or oil, it would create a covering of the metal and the force field of the shield would cease the ‘iron oxide’ to break through the coverings and the rust would disappear inside since the type of varnish, oil would also act as a remover because of the covering which is besieging it.
Iron and steel rust when they come into contact with water and oxygen. Both of it are vitally needed for rust to occur.. The iron reacts with these two substances to form hydrated iron (III) oxide, which is also called rust.
ReplyDeleteRust is an irreversible change because the iron and oxygen have combined on an atomic level creating the compound iron oxide and you would need to manipulate it on the atomic level to separate it.
Varnish and oil etc can be used to prevent rust because the coating of it acts as a shield which ceases it from ruining the iron and steel. A coat of paint can prevent rust on metallic surfaces such as metal gates etc, glue acts in a similar way.
I think to prevent rust you need to paint the whole school with whatever paint you want it to be in everywhere because paint prevents rust from appearing and the bits that you have left are going to have the most rust.
ReplyDelete- Rusting occurs when an iron surface meets oxygen and water, when air reaches water it creates a chemical reaction which creates rust .
ReplyDelete- Stainless steel cannot rust ; by using it your item will not rust- for example most sinks are made out of it and most sinks do not rust.
- Rusting is an irreversible change because the iron and oxygen have combined on an atomic level creating the compound iron oxide and you would need to control it on the atomic level to separate it.
Rusting occurs when a substance like iron has gained access to air and water at the same time. If you were testing if a nail rusts and the nail can rust normally the nail would be in a plastic pot. After 24 hours the water should change colour to be a brownish orangey colour which means the nail has partially rusted. In 148 hours the water should be a complete brown colour which shows tat the nail has rusted.
ReplyDeleteIron and steel rust when they come into contact with water and oxygen. Both water and oxygen are needed for rusting to occur. In the experiment below, the nail does not rust when air or water is not present. Remember that 21 per cent of the air is oxygen.
ReplyDeleteGalvanising is a method of rust prevention. The iron or steel object is coated in a thin layer of zinc. This stops oxygen and water reaching the metal underneath - but the zinc also acts as a sacrificial metal. Zinc is more reactive than iron, so it oxidises in preference to the iron object.
Rust is irreversible because it is caused by Oxidation and you would have to manipulate it on the atomic level to separate it. THAT IS REALLY DANGEROUS UNLESS YOU WEAR SAFETY EQUIPMENT!!!!!!!!!!!!!!!!!!!!!
VALLABH.N :)
Rusting occurs very often if iron is in contact with water and oxygen. They rust faster if it is salty water or acidic rain. Aluminium,on the other hand doesn't corrode easily because its surface is protected by aluminium oxide.
ReplyDeleteTo prevent rust you can use paint for making it a good colour and protecting it from rust. Varnish on the other hand can be used for a different item such as wooden tables it all depends on common sense and so rust can be prevented
Rusting occurs when iron comes into contact with water and oxygen. When water falls onto iron, it reacts with the oxygen in the water and forms iron oxide-this is rust. The drop of water turns reddish in colour and the rust is suspended in the water. When the water drop evaporates, the rust remains there and forms a reddish coat on the iron itself.
ReplyDeleteWe could prevent rusting by oiling, greasing, painting and galvanising. We can oil chains, paint and grease cars and galvanise metal.
Rusting is an irreversible change, because the iron and oxygen have combined. This is a strong mixture. Once this has mixed, it can’t change back-this is called irreversible.
Rust occurs when oxygen, water and certain metals mix, causing a chemical reaction called oxidation. An example of some metals that corrode is iron or steel. To corrode just a little in a day, the steel or iron piece would need just normal water to absorb, of course still at least one part of the metal emerged from the water. Although if you would want the metal to rust quite a lot in one day, a way to make the oxidation process would be to use salt water.
ReplyDeleteToday we will be debating whether holidays should become longer. We will review the for and against points of the argument. We will look at the effects of this possible change on the lives of teachers, pupils and parents and carers.
ReplyDeleteFOR:
- Longer holidays may relax the child so that they come back to school more refreshed and ready to learn.
- Longer holidays relieve stress.
- Teachers may need longer holidays to rest and unwind and use the time to plan lessons for the future.
- More flexibility for families to travel abroad, without the 'school holiday' ticket prices.
AGAINST:
- Longer holidays may make children feel lazy towards going back to school to learn.
- To much recreation time may affect concentration in lessons
- Working parents may have a problem taking more time off work to spend caring for children.
- Children need to be in school learning so that they may have a good career, and be competitive with other education systems in the world.
There are several ways to prevent iron and steel rusting. Some of these work because they stop oxygen or water reaching the surface of the metal:
ReplyDeleteoiling - for example bicycle chains
greasing - for example nut and bolts
painting - for example car body panels
Iron and steel rust when they come into contact with water and oxygen. They rust faster in salty water or acid rain.
Iron and steel rust when they come into contact with water and oxygen. Both water and oxygen are needed for rusting to occur.
Rust can occur when you leave your bike or anything metal in the rain. A way to prevent rust is to probably build or order a shed. But that's not the only way. You can probably use paint and oil to prevent rust. They are probably the best solution to prevent rust
ReplyDeleteRust forms due to the reaction of oxygen dissolved in water with iron. Rust is a generic term to describe different oxides.
ReplyDeleteA traditional method used to prevent rusting of ships is to seal the surface with paint, grease, plastic, tin etc. as in the barrier method or to ‘sacrifice’ a piece of more reactive metal, such as zinc or magnesium, that is attached to the iron but not usually covering it, as in the electrolytic method.
Forming an air-tight barrier by sealing the iron surface with paint may improve the appearance of a ship.
Rust is an irreversible change as rust can't be undone.