Ai giúp mk với *1) Cho các nguyên tố: Mg (Z=12), Na (Z=11), K (Z=19), Al (Z=13). a/ So sánh tính kim loại của các nguyên tố trên. b/ So sánh tính bazo của các hidroxit. *2) Cho các nguyên tố N (Z=7), Si (Z=14), P (Z=15). a/ So sánh tính phi kim của các nguyên tố trên. b/ So sánh tính axit của các hidroxit tương ứng

1 câu trả lời

Đáp án:

 1)

a)K>Na>Mg>Al

b)KOH>NaOH>Mg(OH)2>Al(OH)3

2)

a) N>P>si

b) HNO3>H3PO4>H2SiO3

Giải thích các bước giải:

1)

a)

Ta có Na Mg và Al ở cùng chu kì =>Tính kim loại Na>Mg>Al

Na và K ở cùng nhóm nên tính kim loại K>Na

=>K>Na>Mg>Al

b)

Tính bazo của hidroxit: KOH>NaOH>Mg(OH)2>Al(OH)3

2)

a)

Ta có Si và P ở cùng chu kì nên tính phi kim của P>Si

P và N ở cùng nhóm nên tính phi kim của N>P

=> N>P>Si

b)

HNO3>H3PO4>H2SiO3

Câu hỏi trong lớp Xem thêm

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