NATRI SALICYLAT

Natrii salicylas

 

 

 

 

C7H5NaO3 P.t.l: 160,1

Natri salicylat la natri 2-hydroxybenzencarboxylat, phai cha t 99,0 en 101,0% C7H5NaO3, tnh theo che pham a lam kho.

Tnh chat

Bot ket tinh trang hoac tinh the khong mau hay hnh vay ong anh, khong mui.

De tan trong nc, hi tan trong ethanol 96%, thc te khong tan trong ether.

nh tnh

A. Lay vai hat che pham a vao ngon la khong mau, ngon la se chuyen thanh mau vang.

B. Lay khoang 10 mg che pham hoa tan trong 10 ml nc, them 1 giot dung dch sat (III) clorid 3% (TT), se xuat hien mau tm.

C. Hoa tan khoang 1,5 g che pham trong khoang 20 ml nc, them 6 ml dung dch acid nitric 16% (TT), se xuat hien tua trang. Loc, ra tua bang nc va say kho trong bnh hut am vi acid sulfuric (TT), iem chay cua acid salicylic thu c t 158 en 161 oC (Phu luc 6.7).

o trong va mau sac cua dung dch

Dung dch S: Hoa tan 5,0 g che pham trong nc khong co carbon dioxyd (TT) va pha loang thanh 50,0 ml vi cung dung moi.

Dung dch S phai trong (Phu luc 9.2) va khong c co mau am hn mau mau VN6 (Phu luc 9.3, phng phap 2).

Gii han acid

Hut 20 ml dung dch S, them 0,1 ml dung dch o phenol (TT), dung dch co mau vang. Mau cua dung dch phai chuyen sang mau tm o khi them khong qua 2,0 ml dung dch natri hydroxyd 0,01 M (C).

Clorid

Khong c qua 0,02% (Phu luc 9.4.5).

Lay 5 ml dung dch S, them 5 ml nc va 10 ml acid nitric loang (TT), loc. Hut 10 ml dch loc, pha loang thanh 15 ml vi nc va tien hanh th.

Sulfat

Khong c qua 0,06% (Phu luc 9.4.14).

Lay 2,5 ml dung dch S, pha loang thanh 15 ml vi nc va tien hanh th.

Kim loai nang

Khong c qua 20 phan trieu (Phu luc 9.4.8).

Hoa tan 1,50 g che pham trong 15 ml hon hp gom 5 the tch nc va 10 the tch ethanol 96% (TT). Lay 12 ml dung dch tien hanh th theo phng phap 2. Dung 10 ml dung dch ch mau 2 phan trieu (TT) thu c bang cach pha loang t dung dch ch mau 100 phan trieu (TT) vi hon hp gom 5 the tch nc va 10 the tch ethanol 96% (TT), e chuan b mau oi chieu.

Mat khoi lng do lam kho

Khong c qua 0,5% (Phu luc 9.6).

(1,000 g; 100 105 oC).

nh lng

Can chnh xac khoang 0,130 g che pham, hoa tan trong 30 ml acid acetic khan (TT). Chuan o bang dung dch acid percloric 0,1 N (C). Xac nh iem ket thuc bang phng phap chuan o o ien the (Phu luc 10.2).

1 ml dung dch acid percloric 0,1 N (C) tng ng vi 16,01 mg C7H5NaO3.

Bao quan

ng trong chai lo kn, tranh anh sang.