Answer:
Here's what I get.
Explanation:
(a) F, Cl, Br, and I are called halogens (salt formers)
(i) They are placed in Group 17, the Group just before Group 18 (the noble gases), because they need just one more valence electron to get a noble gas electron configuration.
(ii) At room temperature, iodine is a lustrous, purple-black solid that melts to form a deep violet liquid at 114 °C.
Double pressure and you get the volume.At constant temp. volume =5L
P1V1=P2V2
100 times 2=200timesV2
V2=1000/200
V2=5.0l
Moon reflects the light frim the sun, thats why we are able to see it and it shines in the night. But, we know that Earth revolves around Sun and Moon revolves around Earth. During this revolution, Earth and Moon comes in a position when Earth is in the middle of the Moon and Sun. So, it blocks the light of Sun frim reaching Moon. Hence, we see no reflection and it causes Lunar eclipse.
Protons and neutrons are in the nucleus (the center of an atom), but electrons are not.