Question

Write an explanation.

1. Group
2. Period
3. Atomic radius
4. Electropositivity
5. Electronegativity
6. Balanced equations
7. Endothermic reaction
8. Critical angle
9. Center of curvature of the lens
10. The optical center of the lens.
11. Principal focus
12. Focal length
13. Principal axis
14. Minimum Distance of distinct vision
15. Farthest Distance of distinct vision
16. Magnification
17. Power of accommodation
18. Persistence of vision
19. Alkane​

Answer 1

Answer:

1 ans Group 1 is composed of hydrogen (H) and the alkali metals. Elements of the group have one s-electron in the outer electron shell. Hydrogen is not considered to be an alkali metal as it is not a metal, though it is more analogous to them than any other group. This makes the group somewhat exceptional.