False, that only applies to water as far as I know, but I know for a fact that gold does not melt at 0 degrees Celsius
Answer : The mass of water produced will be 32.78 grams.
Explanation : Given,
Mass of 
= 21.9 g
Molar mass of = 72.15 g/mole
Molar mass of 
= 18 g/mole
First we have to calculate the moles of .
Now we have to calculate the moles of .
The balanced chemical reaction will be,
From the balanced reaction we conclude that
As, 1 mole of react to give 6 moles of
So, 0.3035 moles of react to give 
moles of
Now we have to calculate the mass of .
Therefore, the mass of water produced will be 32.78 grams.
Shape
A gas is shapeless all other things being equal. It will, if put in a container, occupy every part of the container.
A liquid could also be thought of shapeless. If put in a container, it need not occupy the entire container. It will occupy as much as its calculated volume will permit it to occupy.
A solid will only occupy its original shape.
Volume
A gas will occupy whatever container it is put in within limits. You cannot put a 72 mols of gas in a mm^3 container without some amazing ability to apply a lot of pressure.
A liquid will occupy a volume determined by its density and mass. In general liquids cannot be compressed.
Whatever volume a solid has to start with, it will retain that volume all other things being equal.
This is actually very hard to describe.
Answer:the Boundary of an advancing mass of warm air, in particular the leading edge of the warm sector of a low-pressure system.
Explanation:
The answer is NO. During combustion of hydrogen, water is produced as an end product. The chemical formulae for combustion of hydrogen are:
2H2 + O2 -->2 H2O
another advantage is that the whole of the fuel load is combusted hence little wastage. This has made the fuel advantageous in its use as rocket fuel since there is no baggage fuel.
