Primarygun

How about alloy of metal? Copper(II) sulphate is soluble in water and in sulphuric acid, isn't it? Why does it becomes insoluble when the water of crystallization of hydrated copper(II) sulphate is drawn by con. sulphuric acid? Moreover, when does copper(I) or copper(II) ion becomes green in colour? In which solution? Aqueous Copper(II) nitrate?

Tell them recycling of metal is necessary.It can help save other resources, such as water, it helps conserve natural resources and thus protect wildlife's habitats. Also, it helps to reduce land pollution as metals are non-biodegradable. You may find out the history of extraction of metals, methods, benefits to human....

No. What are the exact meaning of drivers? Window XP, maybe, the update are always named as " Major update" I'm sad that I didn't take notice on the numbers. My computer has two memory sticks. I've tried to remove one of them and start booting my computer. Neither them has no faults, I think.

The ions of this covalent compound with simple molecular structure combine together when water leaves? Then, the gas leaves?

What happens if I boil a beaker of hydrochloric acid ?

When I boot up my computer, a blue screen appeared. It tells me that my computer has dump of physical memory.What should I do?

A triangle with 7.5 cm , 12.5 cm and 10 cm. My teacher hasn't taught us cosine law or sine law or heron law. This question appears in a chapter of property of circle,simple properties of circle. I have learnt the above three laws so I can find a lot of method to solve it but I lack a method without using these untaught things.

I think I will travel around the world later when I grow up. That enrichs my knowledge a lot.

How much knowledge do all members of the forum have? Enough to solve any questions given by a professor in an university, college? Or just for some common problems.

or Some past exam papers.

Yesterday, I have a thought. When a bomb explodes, it naturally destroys the surrounding objects, such as trees, houses, cattle. The damage always spreads to a far distance, but the damage to the ground is much less than it. Maybe only 1-fortyth to it. I guess it's because the force provided by certain bomb strips hitting the ground is smaller than the frictional force. Am I correct?

I am glad to hear that you are currently asking many Maths Olympaid questions. In HK, these kinds of questions are called" Planting trees Questions". When you take the difference between the pages, you miss one. In fact, you miss the first page or the last page as difference regards to interval. You need to add one to the difference as you want both first and last. Take difference only when you only want first or last. Minus one when you don't want either the first or the last one. May I know what does grade 4 refer to?

It is said that practise makes perfect. Doing a lot of good exercises really help you to consolidate your skills, abilities to solve questions. Nevertheless, tricky and open-end question is slightly available for students in those thin text books. Regarding to our scientific knowledge here, I suggest that we create a region for storing some interesting and I mentioned above for sharing purpose. In reality, I am short-sighted and I wear glasses all the time. Perhaps, at the moment, I am really indeed "SHORT-SIGHTED" at my current suggestions.

During anaerobic and anaerobic respiration, energy is released and used to form ATP molecules in cytoplasm. Which can release more energy in that region?

is x a new symbol? I think I need a clarification.

How did Mr. Newton find out Newton's 3rd law? He illustrated the things on the earth first or the universal attractions between any two objects first?

There are two possible answers. Perhaps, teacher day tells us which month it usually falls. Otherwise, the question has faults.

The information given is not detailed enough. Please specify in which months. This kind of question is always be tested in maths primary school competitions.

Yes, why are oval orbits?

For a triangle, 3 sides are given. What's the radius of its circumcircle? Are we able to get it without using cosine law or sine law or heron formula?

I press "Home" to search for new posts and I click my name to look for the new reply in my thread.

I know a little bit of acid, but I always hear of its strong corrosive ability. I thought it can damage things which does not contain water too. With this mind, I thought calcium sulphate solid was easily decomposed by any acid. Now I recognise acid reaction is only kinds of fast displacement reaction in the presence of water. Yes, that's alkalis,the one neutralizes acid.

What's the reaction between alkalis and some reactive metals? I don't have that reaction in my books/ Why doesn't sulphuric acid react with calcium sulphate?

so aq?

but it is not very ionizable.