Answer: Im not sure but I think it is false.
Explanation:
Physical change
iron nail have high melting point, thus, when it is heated, it will not melt very easily.
chemical change
iron nail can rust due to the exposure to the air(oxygen). iron in the nail and oxygen in the air will react together to form iron oxide(rust).
furthermore, the reaction is irreversible.
Answer:
For one atom of lithium -6 I will need_16.85____ atom of lithium -7 for an average atomic mass of 6.944 .
Explanation:
1 ) Let required atom be m .

6 + 7m = 6.944 + 6.944m
7 m - 6.944 m = .944
.056 m = .944
m = 16.85
Answer:
63 moles of carbon atoms, 115.5 moles of hydrogen atoms, and 57.75 moles of oxygen atoms i believe :)
Answer:
The Moon has an atmosphere.
Explanation:
The Moon has an atmosphere, but it is very tenuous. Gases in the lunar atmosphere are easily lost to space. Because of the Moon's low gravity, light atoms such as helium receive enough energy from solar heating so that they escape in just a few hours.