2. Укажіть групу речовин, яка містить лише кислоти. А) Р 2 О 5 , РН 3 , Н 3 РО 4 ; Б) НСl, H 2 CO 3 , H 3 PO 4 ; В) SO 2 , H 2 SO 3 , Li 2 SO 3 ; Г)MgCl 2 , Na 2 SO 3 , K 3 PO 4 .
My best and memorable day in my life is considered the new year! on the eve of myalways covers the strange feeling that something needs to happen and joyfulmagical. throughout the festive atmosphere , all selected beautiful christmas tree , buydifferent fruits , sweets, prepare gifts for loved ones. we begin preparing for the holiday in advance. clean the house , decorate the christmas tree ,decorate the room with balls, garlands, beautiful toys. mom always cooksfor the holiday table something unusual and very tasty. i try not to sleeptime of arrival of the new year under the chiming clock . after the final blow on the streetfireworks begins , which can last for an hour ! we usually have fun ,hold various contests , dance, sing . it's really fun ! especially good when new year's eve worth frosty snowy weather . inwindows of all the houses flashing colored lights . celebrating and having fun .apparently, due to the fact that the new year - a general holiday , celebrate it so fun!
Fe2O3 Fe(3) O(2)
2 4Al2(SO4)3. 4 молекулы сульфата алюминия. 8 атомов алюминия,
3 атома серы, 12 атомов кислорода.
5Mg3(PO4)2. 5 молекул Ортофосфата магния. 15 атомов магния,
2 атома фосфора, 8 атомов кислорода.
3 ZnI2 → Zn + I2 разложения
4Li + O2 → 2Li2O соединении
3Zn + 2H3PO4 → Zn3(PO4)2 + 3H2↑ окислительно- восстановительная
FeCl3 + 3NaOH → Fe(OH)3 + 3NaCl замещения
4 3 г. х
2Zn + O2 = 2ZnO
65 г/моль 81 г/моль
130 162
m(ZnO)=3*162/130=3,7 г
5 М(K2SO3) = (2*39)+32+(16*3)=158 г/моль
M(Mg3(PO4)2) = (24*3)+(31*2)+(16*8)=262 г/моль