NH4NO3(s): ∆Hf = -365.56 kJ ∆Sf = 151.08 J/K.
NH3(g): ∆Hf = -46.11 kJ ∆Sf = 192.45 J/K.
H2O(l): ∆Hf = -285.830 kJ ∆Sf = 69.91 J/K.
O2(g): ∆Hf = 0.00 kJ ∆Sf = 205 J/K.
b. false
Its False, because in the formation of an ionic compound, an atom gains or loses an electron.
Magnetizing steel is a physical change, not a chemical change because it does not change the chemical composition of the steel.
A chemical change is a change in which new substances are formed. This is because the atoms in the original substances are rearranged to form new atoms or molecules. There is no chemical change when magnetizing steel. For example, when iron rusts, it reacts with oxygen to form a new substance called iron oxide.
A physical change is a change in which the form of a substance is changed, but the substanceitself is not changed. For example, when you melt ice, you are changing the form of water from a solid to a liquid, but the water itself is not changed.
When you magnetize steel, you are simply aligning the magnetic domains in the steel. Magnetic domains are regions of a material that have a net magnetic field. When the magnetic domains are aligned, the steel becomes magnetized.
Magnetizing steel does not change the chemical composition of the steel. The steel is still made up of the same atoms, and the atoms are still arranged in the same way. The only difference is that the magnetic domains are aligned, which gives the steel its magnetic properties.
To know more about Magnetizing steel here
#SPJ6