The property of liquid oxygen that makes it especially difficult and potentially harmful to work with at home would be its cryogenic temperature. Liquid oxygen is being produced from the compression of oxygen gas to -196 degrees Celsius. As you can see, it has a very cold temperature that is why it used in cryogenics. Although liquid oxygen is non-toxic to humans, it would cause burns that are severe when being touched. Also, it would make certain materials brittle and unstable. Another property that makes it dangerous for use at home would be that it is very flammable. Proper handling is a must for this substance.
Explanation:
Electromagnetic wave Wavelength
(1) Microwave = 1 m to 1 mm =
to 
(2) Ultraviolet = 10 nm to 400 nm
(3) Radio waves = 1 mm to 100 km =
to 
(4) Infrared = 700 nm to 1 mm
(5) X-ray = 0.01 nm to 10 nm
(6) Visible = 400 nm t0 700 nm
a) In order of increasing wavelength:
: 5 < 2 < 6 < 4 < 1 < 3
b) Frequency of the electromagnetic wave given as:

= frequency
= Wavelength
c = speed of light

So, the increasing order of frequency:
: 3 < 1 < 4 < 6 < 2 < 5
c) Energy(E) of the electromagnetic wave is given by Planck's equation :


So, the increasing order of energy:
: 3 < 1 < 4 < 6 < 2 < 5
Use your head or a formula website.
Answer:
Th is the symbol for element Thorium.
Mg is magnesium while Mg 2+ is magnesium Ion. Judging from periodic trends, atomic radius is one half the distance between the atoms of two covalently bonded atoms. It decreases as elevtrons are added to valence shells. That means, across the period it increases and down the group it decreases. Making Mg2+ smaller.
Electronegativity is the energy needed to take an electron in the gaseous state. Florine is more electron negative that lithium. It increases across the period and decreases down the group. Except in the Noble group.
Explanation: