PH~M QUOC TRUNG • PH~M TRU<1NG

Hu'ONG DAN GIAI ' ~

BAITAP •

•

? ~

THEOCHUDE

'- ~ ? , A

NHA XUAT BAN GIAO Dl)C VI~T NAM

    

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Umg ti CPDV xua't ban Giao d1.1c Gia Djnh- Nha xuii't ban Ghio dvc Vi~t Nam giii' quy~n cong bO' hie phii'm.

79-20 I 0/CX ll /77 -40/GD Ma so: T8H3l MO-D TN

····· ................................ .. ...... Ll11: NOI Diu .................................. .. .... ...... .. .... .

Theo chuang trinh Trung h9c, h9c sinh lap 8 l&n d&u tien lam quen vai m6n Hoa h9c, nen chdc chdn buac d&u se it nhi~u ba nga. Nhlim giup cac em h9c sinh lam quen vai cac chil d~ bai t¢p, h~ thong hoa kien thuc cilng nhu rim luy~n ki nang suy lu¢n Hoa h9c, chung t6i bien so(Ln cuon HUONG DAN GIAI BAI

TAP HOA HQC 8 - THEO CHU BE. Tung xodn trong cuon sach nay duqc viet theo chuang trinh va Sach giao khoa Hoa h9c 8. Trang m8i xodn g6m c6 3 ph&n :

• TOM TAT Li THVYET

• BAI TA.P THEO CHU DE • HUONG DAN GIAI BAI TA.P

Trang tung chu d~, d~u c6 Bai t~p m§.u va Hu6'ng dan giai. Ngay duai Bai t¢p mdu la cac Bai t~p ap dt,mg nhlim giup cac em rim luy~n ki nang lam bai.

Chung t6i hi VQng cuon sach se giup ich ph&n nao cho cac em h9c sinh bdt d&u lam quen vai Hoa h9c va yeu thich m6n Hoa hQC.

Mgc du da co gdng bien so(Ln, nhung kh6 tranh khoi nhung sai sot ngoai y muon. Chung t6i rat mong nh{j,n dU(/C y kien dong gop xay d7!ng tit phia b(;tn dQC.

Mqi y kien dong g6p xin vui long gui ve Ban Khoa hqc tl,l nhien- Cong ty c6 phon Dich vv xu6t ban Gi6o dvc Gia E>inh - 231 Nguyen Van Cu, Qu¢n 5, Thanh ph6 H6 Chf Minh ho¢c qua email khaithacbanthao@yahoo. com.

TAC GIA

3

MQT SO D~NG C~ THi NGHI~M VA Bll~U TU'~NG TRONG HOA HQC

Betcher Erlen PhEfu IQC

Pheu chiet Ong nghi~m

Dechay D¢c Ph6ng xc;t

4

    

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§1. CHAT

A. T6M TAT Ll THUYt:"f

MQi v~t the xung quanh ta deu duqc t~o nfm tu m(lt ho~c nhieu cha t. Moi chat c6 nhung tinh chat v~t li va tinh chat hoa hoc nha t d!nh.

Han Tr6ng - M;i i (tll nhie n) Chen - ora u6ng tra (nha n (i:JO)

1. V~t th~ hf nhien. V~t th~ nhan t<,to

Vt;it th ~' llf nhien Vt;it th ~' nhan l(;w

v~tthe do thien nhien t~o V~t the do con nguai t~o ra gQi la ra gQi la v~t the tt.j nhien. v~t the nhan t~o.

2. Tinh chat cua chat

a. Tinh chat vt;it li

Cac tinh chat k.hong c6 k.ha nang lam bien doi thanh chat k.hac nhu : tr~ng thai Cnin, long, khi), mau s1'ic, mui , vL d<;> dlin di~n, d9 dlin nhi~t, d(l tan, d(l cling, nhi~t d(l n6ng chay, nhi~t d(l soi, khoi luqng rieng, nhi~t dung rieng, ... gQi Ia tinh chat v~t li.

5

Thi di.!-. d di~u ki~n thuang :

- Ca t a tr~ng thai nin ; nuac a tr~ng thai long ; oxi a tr~ng thai khi.

- Vang mau vang ; dong mau do ; nhom mau triing.

- dt v~ cay ; duang v~ ng<,>t ; muoi v~ m~n .

-Bong dan di~n nl't tot ; than chi khong dan di~n.

b. T inh cha't h oci h9c

Cac tinh chat c6 kha nang bien d6i thfmh chat khac nhu : tinh de chay, kha nang phan huy, kha nang ket hqp vai chat khac 000

Thi di.!-.

-Con de chay, khi chay t~o thanh khi cacbonic va hai nuac.

- Nuac thi khong thr; chay.

- Siit dg ngoai kh6ng khi lau ngay b~ gi set (ket hqp vai OXl t~o

thanh chat khac).

3. Cha't tinh khiet. Hbn hqp. Tach ch ~i't

a. Clui t tinh khiet. Han hap

6

Ch<it tinh khiet Han hr;p

Chat khong c6 Ian chat nao Hai ho~c nhi~u chat trqn Ian khac g<,>i la chat tinh khiet. vao nhau g<,>i la h6n hqp.

Thi d i.!-. Nuac tinh khiet dung Thi d i.!- . Nuac bign ; khong khi. trong y te.

b. T eich cha t

Dt!a vao stf khac nhau v~ tinh chat v~t li c6 thg tach cac chat ra khoi h8n hqp.

Chie't L9C

Tach cac chat Tach chat long khong d.n ra khoi tan vao nhau chat long. ra khoi h8n hqp.

-

Chung cat

Tac h cac chat Ion soi

g c6 nhi~t d(> khac xa nhau hoi h8n hqp chung.

ra k cua

Ket tinh

Tach cac chat c6 d(> tan khac nhau ra khoi h8n hqp.

B. sAl T ~ THEO cH0 E>~

chu d~ 1. Phan bi~t cha·t voi v~t the

a.i=~J! Xet eric u¢t the sau : (1) xe dq.p ; (2) may_ bay ; (3) tui nilon ; (4) cuon )JC::JL srich ; (5) Gc;w ; (6) Trai Dat ; (7) may. It nhat m{)t chat niw dii lam

nfm tung u¢t the d6 ?

··································· · ···················· ···· ··········· ·· ················· ············~~

(1) Xe d~p duqc lam nen tU sAt.

(2) May bay duqc lam tU nhom. .

(3) Tui nilon duqc lam tU nht,fa (chat deo).

( 4) Cu6n sach duqc lam tU giay (xenluloza).

(5) G~o duqc t~o nen tU tinh b(>t.

(6) Trai Dat t~o nen tU dat, da, nu6'c ...

(7) May t~o nen tU nu6'c.

~l Lay 2 thi dl! u~ v¢t th~' duc;rc tq.,o nen tit : ) J ·

11: . . a. Sdt b. Nh6m

c. Dong d. Cha't deo e. dat set f thuy tinh g. cacbon.

~ -···················································································· · ········ ········~~ a. 2 v~t th€ duqc lam tU sAt la : (1) xe Ilia ; (2) duang ray.

b. 2 v~t th€ duqc lam tU nhom la : (3) n&i nhom ; (4) may bay.

c. 2 v~t th€ duqc lam tU d&ng la : (5) day di~n ; (6) huy chuang dong.

d. 2 v~t th€ duqc lam tU chat deo la : (7) tui xach ; (8) ghe nht,fa.

e. 2 v~t th€ duqc lam tU dat set la : (9) ch~u tr&ng hoa ; (10) g~ch .

f. 2 v~t th€ duqc lam tU thuy tinh la : (11) kieng soi ; (12) cl'ta kinh.

g. 2 v~t th€ duqc lam tU cacbon la : (1) nhan kim cuang ; (2) c~,~c than.

7

1.1. Xet cac v<%t thg sau : (1) xe giin may ; (2) cao oc ; (3) tO' bao ; (4) dia

VCD ; (5) dub'ng an ; (6) M~t Trang ; (7) h~t suang. it nhat mqt chat

nao da lam nen tUng v<%t th~ d6 ?

1.2. Lay thi d1,1 v~ v<%t th~ duqc t~o nen tU :

a . thuy ngan

c. dub'ng

e . xi-mang

g. b~c.

b. th~ch cao

d. nhlfa

f. vang

~· Phan bi~t u¢t thi tl! nhien, u¢t thi nhan tq.o tiL ccic u¢t th i sau : ·' (1) Sao Hom (2) chua Mi)t Ci)t

(3) Kim Tl! Thcip (4) Vq.n Li Truong Thanh (5) v?nh Hq. Long (6) scich Binh Phcip Ton Tu (7) may bay (8) c&u uong (9) may (10) ccii du .

......................................................................................................... ~&

V<%t th~ w nhien gom : (1), (5), (8), (9).

V<%t th~ nhan t~o gom : (2), (3), (4), (6), (7), (10).

1.3. Phan bi~t v<%t th~ W nhien, v<%t th~ nhan t~o tU cac v<%t th~ sau :

(1) thap Eiffel (2) dqng Phong Nha

(3) sao choi (4) tuqng dai Le-nin

(5) kenh dao Panama (6) Bi€n Ho

(7) d.u My Thu<%n (8) dao Phu Quoc

(9) mo dau (10) nha may di~n h~t nhan.

8

chu d~ 3. Tach chat

(i-af4,Trong khong khi c6 2 thanh ph&n chinh la oxi va nita. Oxi c6 nhi~ t _.,.,/ - d(J s6i la - 183°C con nita c6 nhi~t d(J s6i la -196°C. Trinh bay

phuang phap de' tach 2 khi oxi va nita rieng bi~t .

.................................................................................................... ~~

Lam l~nh khong khi d~ dua khong khi v~ duoi d~ng chat long.

- Dung phuo'ng phap chung cat, tang nhi~t d<) tU tU den -196°C thi khi nita soi va boc hai ra truoc (khi nita boc hai, nhi~t d<) van khong tang) ; con oxi van con niim duoi d~ng chat long.

- Hoa hai oxi long se thu duqc khi oxi.

Kh ong khi long ___-.

/(i ;.i Trinh bay phuang phap tach rieng muo'i an c6 ldn nhieu cat .

.................................................................................................... ~~

Dya vao tinh chat muoi an tan trong nuoc, con cat khong tan trong nliOC, nen Slt dt,mg phliang phap l<;>c d~ tach lay muoi an khong COn Ian cat.

- Hoa tan mau muoi nay vao nuoc, khuay d~u thu duqc (A).

- Cho tU tU A vao pheu c6 giay l<;>c, chat long se chay xuong duoi (B) ; con cat khong tan nAm tren giay l<;>c.

- Lam bay hai nuoc (B), ta duqc muoi an.

(A)

(B)

9

f~~~:-1: Trinh bay phuang ph6p tach ri eng ddu an va nuac ra khoi nhau. ·~

....... ::: :: · : · : · : · : ·~~- ........ ...... ...................... .. ........ ...... ............ ...... .... .. ......... ~ ciJ:n

D1iu va mt<k la 2 chat long khong tan vao nhau, nen Slt dt,mg pht.tang phap chiet d~ tach chung ta khoi nhau.

dau

~---mrac

D1iu nh~ han nt.tac nen nflrn tren, rna van thi thu dt.tqc nt.tac trt.tac den khi het nt.tac thi khoa van l~i . Nht.t v~y da tach rieng duqc nt.tac va d1iu.

1.4. Mi)t han hqp gorn c6 2 khi la oxi va hidro. Oxi c6 nhi~t di) soi la -183°C con hidro c6 nhi~t d9 soi la -253°C. Trinh bay pht.tang phap d~ tach 2 khi oxi va hidro rieng bi~t.

1.5. Trinh bay phuang phap tach rieng:

a. dt.tO'ng an c6 Ian cat.

b . h~t lua va vo lua.

1.6. Trinh bay phuang phap tach rieng :

a. xang va nt.tac ra khoi nhau.

b. rna va xang (a di~u ki~n thich hgp).

c. HUONG DAN GIAI BAIT~

1.1. (1) s8:t

10

(3) giay (xenluloza)

(5) dt.tO'ng

(2) xi-rnang

(4) chat deo

C6) dat (7) nt.tac.

1.2. Lay thi d1,1 ve v~t the duqc t~o nen tU:

a. Nhi~t ke thuy ngan.

b. Td.n nha dan th~ch cao.

c. Banh, k~o.

d. Man hinh ti vi.

e. Khoi be-tong.

f. D6 trang sue bilng vang.

g. D6 trang sue bAng b~c.

1.3. V~t the tt,t nhien g6m : (2), (3), (6), (8), (9).

V~t the nhan t~o g6m : (1), (4), (5), (7), (10).

1.4. Lam l~nh hon hqp de dua hon hqp ve dt16'i d~ng chat long.

- Dung phuang phap cht1ng cat, tang nhi~t d9 tU tU den -253°C thi khi hidro soi va boc hai ra trt16'c (khi hidro boc hai, nhi~t d() van khong tang); con oxi van con nilm dt16'i d~ng chat long.

- Hoa hai oxi long se thu duqc khi oxi.

1.5. a. Dt,ta vao tinh chat duang tan trong nt16'c, con cat khong tan trong nt16'c, nen Slt d1,1ng phtJang phap l9c de tach lay dtibng khong con Ian cat.

- Hoa tan mau duang c6 Ian cat vao nt16'c, khuay deu thu duqc (A).

- Cho- tUtU A vao pheu c6 giay l9c, chat long se chay xuong dt16'i (B) ; con cat khong tan nAm tren giay l9c.

- Lam bay hai nt16'c (B), ta duqc duang.

b. Do h~t lua n~ng han vo lua, nen cho mau dn tach rieng vao nt16'c thi h~t lua Hing xuong day, vo lua n6i len tren. Nhu v~y da tach duqc h~t lua va vo lua ra khoi nhau.

1.6. a. Xang va nt16'c la 2 chat long khong tan vao nhau, nen Slt dt,Jng phtJang phap chiet de tach chung ta khoi nhau.

Cho mau dn tach vao binh chiet, do xang nh~ han nt16'c nen nAm tren, rna van thi thu duqc nt16'c trt16'c den khi he't nt16'c thi khoa van l~i. Nhu v~y da tach rieng duqc nt16'c va xang.

b. Ma va xang deu khong tan trong nt16'c, a dieu ki~n thich hqp rna tan trong xang. Khi lam l~nh ve khoang 0°C, rna se de dong tt,J l~i con xang thi khong, sau do tach 16'p rna ra khoi xang.

11

§2. NGUYEN TlJ

A. T6M TAT Ll THUYtf

proton

M6 hinh nguyen tu

Nguyen hi H~t Proton Notron Electron Trang m(lt la h~t vo nhan mang khong mang nguyen ttl cung nho, t~o bai di~n mang di~n tich cac trung hoa proton tich di~n am(-), electron di~n. va dudng tic h. quay xep thanh Nguyen tli ndtron. ( + ). quanh tltng lop. g6m h~t h~t Moi lop nhan va vo nhan. electron t~o ba.i Electron c6 m(lt so electron. c6 khoi electron

htqng nhat d~nh. rat be.

Chuy.

- Trang cung m{)t nguyen tzl : 86 electron luon luon bilng s6 proton.

- Khoi luc;mg ella hQt nhan biing_ kh6i luc;ng nguyen til.

12

    

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B. BAI T .;p 11-iEO CHU f)~

cbu d~ x. xac d!nh sop, so e, so e lop nuoai cling, so lop e

Jfiii}Hay xtic d!nh s6 p, s6 e, s6 e lap ngoili cling, s6 lOpe cda ~ m6 hinh nguyen tu ben. ~

..................................................................................................... ~ ciJ:n

-soP Ia 13.

-So e la13.

- So e IO'p ngoai cung Ia 3.

- So lap e Ia 3.

_,~:f)i~n ucw 6 con thi~u nhilng con so thich hc;p.

Nguyen tii Sop So e So So e So e So e IO'p e IO'p 1 IO'p 2 IO'p ngoai

Nhom

Ltiu huynh

Argon

...................................................................................................... ~ ciJ:n

Ghi nha. So e lap 1 luon luon = 2 (tru cua hidro)

Nguyen tii Sop So e So IO'p So e e IO'p 1

Nhom

Ltiu huynh

Argon

So e lap 2

So e

IO'p ngoai

13

2.1. Xac d!nh so p, so e, so e lap ngoai cung, so lap e cua cac mo hinh nguyen tli sau.

Hinh a Hinh b

2.2. Di~n vao o con thie'u nhung con so thich hqp.

Nguyen tli

flo

photpho

clo

canxi

scandi

sop So e so lap e

So e 1C1pl

Hinh c

So e lC1p2

So e

lap ngoai

chu de z. ve mo hinh nguyen tu

ff;· .... ~Ve mo hinh nguyen ti't czla titan. Biet titan c6 s6 proton la 22 ; 4 lap ~electron; c6 4e lap ngoai cung.

· ····· · · ························· · ········· · ············· · ··· · ······· · ··········· ·· · · · ·· · ·· · ·· ··· ··· · ··· ·~c/J:n

14

50 p

lop 1...--------l-~lS<

lop 2 +-------+~ lop J

lop 4 (ngoai cung)

2.3. Ve mo hinh nguyen tli.

a. cua oxi, bie't oxi c6 so p la 8 ; c6 2 IO'p e ; IO'p ngoai cung c6 6e.

b. cua neon, bie't neon c6 so p la 10 ; c6 2 IO'p e ; l&p ngoai cung c6 Be.

c. cua kali, bie't kali c6 so p la 19 ; c6 4 IO'p e ; ldp ngoai c6 1e.

d. cua crom, bie't crom c6 sop la 24 ; c6 4 IO'p e ; l&p ngoai cung c6 6e.

c. HUONG DAN GIAI BAI T.;p

2.1.

2.2.

Nguyen tli sop So e soiap So e So e So e e IO'p1 lcr' p 2 l&p ngoai

flo

photpho

clo

canxi

scandi

2.3.

cau a cau b Cau c Cau d

15

§3. NGUYEN TO HOA HQC

A.TOMTATLI~

1. Dinh nghia nguyen to hoa hQc

Nguyen to hoa h<?C la t~p hqp nhung nguyen tli cung lo~i, c6 cung so proton trong h~t nhan. V~y so proton la so di[tc tntng cho m<)t nguyen to hoa h9c.

Thi dlf. Trong h~t nhan cua cac nguyen tli c6 so notron khac nhau, nhung c6 cung so proton b~ng 8, thi nguyen tli nguyen to d6 la oxi .

2. Kl hi~u hoa hQc

Ki hi~u hoa h9c bieu dien nguyen to va chi m<)t nguyen tlf cua nguyen to d6.

Thi dlf. 0 la ki hi~u cua nguyen to oxi va 1 nguyen tli oxi.

Ca la ki hi~u cua nguyen to canxi va 1 nguyen tli canxi.

2 nguyen tli canxi thi phai viet la 2Ca.

3. Nguyen tu khoi

16

Nguyen tli khoi la khoi luqng cua nguyen tli tinh b~ng don v~ cacbon . Mbi nguyen to hoa h<?C c6 nguyen tli khoi rieng bi~t.

Thi dlf. Nguyen tli khoi cua cacbon la 12 dvC.

Nguyen tli khoi cua oxi la 16 dvC.

Nguyen tli khoi cua dong la 64 dvC.

Nguyen tli khoi cua b~c la 108 dvC.

B. GIAI BAI T.;p THEO CHU f)~

chu d~ x. Ki hi~u boa hoc. so nguyen tO'

4~. Jf\, Gidi thich y nghia cua cac each vie't sau : )}Wil'lJ 2H ·50 · 7Mg · 13Al · JOAg · 8Ba

' ' ' ' ' .

······························································· ························ ·············~~

2H c6 nghia Ia 2 nguyen tli hidro.

50 c6 nghia la 5 nguyen tlt oxi.

7Mg c6 nghia la 7 nguyen tlt magie.

lOAg c6 nghia la 10 nguyen tlt b~c .

8Ba c6 nghia Ia 8 nguyen tlt bari .

J}f;a~ J} Dung chu s6 va ki hi~u hoa h9c di~n dq.,t ccic y sau : "' ~ a. nguyen t6 natri .

b. ba nguyen til dong c. tam nguyen til brom d. mztai nguyen tillztu hujmh.

r ································································ ········ ····························~~ a. Nguyen to natri viet la Na.

b. Ba nguyen tli d6ng vie t la 3Cu.

c. Tam nguyen tlt brom viet la 8Br.

d. Mttai nguyen tlt lttu huynh viet la lOS.

3.1. Gi~ii thich y nghia cua cac each viet sau :

14N ; 24Mg; 31P; 328 ; 39K; 56Fe ; 65Zn ; 108Ag; 207Pb.

3.2. Dung chu so va ki hi~u hoa h<;>c dien d~t cac y sau :

a. 1 nguyen tlt hidro.

b . 19 nguyen tlt flo.

c. 23 nguyen tlt natri.

d. 27 nguyen tlt nhom.

e. 31 nguyen tlt photpho.

f. 64 nguyen tlt d6ng.

2A. HVCJNG DAN GIA I BA I T,i.P HOA HOC 8-TH£0 CHU D,;

chu de z. Nguyen tu khoi. xac dinh ten nguyen to

Q Tim nguyen til: (duC) czla: a. ll nguyen til: natri. b. 16 nguyen til: luu hujmh. c. 20 nguyen til: canxi. d. 26 nguyen til: sdt. e. 35 nguyen til: brom.

·········································································································~&

a . Nguyen tti khO'i cua 11 nguyen tt1 natri la :

b. Nguyen tti khO'i cua 16 nguyen tti h.tu huynh la :

c. Nguyen tti khO'i cua 20 nguyen tti canxi la :

d. Nguyen tti khO'i cua 26 nguyen tti s~t la :

e. Nguyen tti khO'i cua 35 nguyen tti brom la :

11x23 = 253

16x32 = 512

20x40 = 800

26x56 = 1456

35x80 = 2800

.£jiftso scm~ khoi luc;mg czla nguyen til: canxi nQ,ng hay la nhf! han bao )~j!V nhieu Zan cac nguyen til: sau ?

a. hidro c. dong

b. oxi d. b<;~-c e. uang .

..... .................................................................................................... ~&

a . Theo d~ => Mea = 40 = 40 MH 1

=> V~y 1 nguyen tti canxi n~ng gap 40 Mn 1 nguyen tti hidro.

b. Theo d~ => Mea = 40 = 2,5 M 0 16

=> V~y 1 nguyen tti canxi n~ng gap 2,5 Mn 1 nguyen tt1 oxi.

c. Theo d~ => Mea = 40 = 0,625 Mcu 64

=> V~y Ca nh~ han va chi bAng 0,625 Mn Cu.

d. Theo d~ => Mea = 40 = 0 37 MAg 108 '

=> V~y Ca nh~ han va chi bAng 0,37 Mn Ag.

e. Theo d~ => Mea = 40 = 0,203 MAu 197

=> V~y Ca nh~ han va chi bAng 0,203 Mn Au.

18 26. HlJONG DAN GIAI SA l T,i.P HOA HOC 8-THEO CHU D~