Question

answer this 8 ; 9 question all I will make you brilliant

Answer 1

when quick lime reacts with water it forms slaked lime and hydrogen gas

Answer 2

8)a)when water is boiled Change in physical State is observed i.e., liquid state to gaseous state. it is reversible process
b) when a paper is burnt chemical is observed bucz the chemical state of paper changes i.e., from paper to ash, which is a solid residue of combustion . it is irreversible process.

c)The water level remains the same when the ice cube melts. 

A floating object displaces an amount of water equal to its own weight. Since water expands when it freezes, one ounce of frozen water has a larger volume than one ounce of liquid water. A completely submerged ice cube weighing one ounce, for example, displaces MORE than one ounce of liquid water. The cube will rise until the volume remaining under the surface displaces only one ounce of water. 

If you could remove the ice cube and leave a 'hole' in the water where the cube used to float without disturbing the surrounding water, that hole would take exactly one ounce of liquid water to fill. Let the ice cube melt. Since it is now one ounce of liquid water, putting it back into the 'hole' will exactly fill it and leave the remaining water undisturbed.


d)Ammonium chloridedecomposes when heated, but condenses in the cooler area at the top of the test tube. This is a reversible reaction, where the ammonium chloride decomposes into the gasesammonia (NH3) and hydrogen chloride(HCl).
e)they will get rusted due to the effects of oxygen and water on it.

f)it is a physical change - the sugar is still sugar, but rather than being in a solid state, it changes to liquid.

g)