It’s 1 or 3 sorry if this is wrong
Ok heres what i know, one of the reasons why visible light will pass through glass but not through other materials is because the molecules in glass require more energy than average to push electrons from one level to another. Photons in visible light simply do not have enough energy. Only photons of light with shorter wavelengths, such as those that make up ultraviolet light, have the ability to change the electrons in glass. This is why ultraviolet light is unable to pass through glass. Lol im in 6th grade this is all i know ! :)
Answer:
1. the group number of sodium is 1 and it is a metal
2. the group number of helium is 18 and it is a nonmetal
3. the group number of iodine is 17 and it is a nonmetal
4.the group number of calcium is 2 and it is a metal
5. lithium has similar properties to potassium
6. calcium has similar properties to magnesium
7. neon has similar properties to xenon
8. Iodine has similar properties to chlorine
