Answer:
(a) (i) All the elements of a group have similar chemical properties because they have same no. of valence electrons in their outermost shell. (ii) All the elements of a period have different chemical properties because they have different no. of valence electrons in their atoms.
The Answer is A
This is because sodium needs to give off one electron to be stable, form these options the only element that needs to take one electron to be stable is fluorine thus A is the answer
Answer:
Consider how the speaker begins the speech, the support given in the body of the speech, and how the speaker concludes. Listen for changes in tone. Listen for how the speaker uses delivery techniques such as pauses, pace, voice, metaphors and symbolism, repetition and parallelism, and vocabulary.
Explanation:
Answer:
C. fluorine (F) and chlorine (Cl)
D. arsenic (As) and antimony (Sb)
Explanation:
In the periodic table , all the elements are arranged according to the atomic number ,
and the elements are placed in groups and periods ,
The elements with similar chemical and physical properties are placed in a common group .
The elements present in the same group have the same number of valence electrons in the valence shell .
Hence , from the given options ,
fluorine (F) and chlorine (Cl) belongs to group 17 with 7 valence electrons in the outermost shell .
arsenic (As) and antimony (Sb) belong to group 15 with 3 valence electrons in the outermost shell .
