Multiple choice question

fjDr fjDr LFkkuks LFkkuks dh dh iwfrZ iwfrZ dhft;sA
dhft;sA
fjDr LFkkuks dh iwfrZ dhft;sA Fill in the blanks
5 tc Qkjfed vEy dks lkUnz H SO ds lkFk xeZ fd;k tkrk gS rks -------------
2 4
curk gSA
When formic acid is heated with concentrated H 2 SO 4 then it forms ..............
6 QSfjd vkWDlkbM dh v'kqf) okys ckDlkbV ds 'kks/ku gsrq ------------ fof/k dk
iz;ksx fd;k tkrk gS\
Boxite having impurities of ferric oxide is purified by the ........... method?
7 tc ,Y;wehuk esa Fe O ,oa SiO nksuks izdkj dh v'kqf);k¡ mifLFkr jgrs gSa rc
2 3 2
bldk 'kks/ku -------------------- dh fof/k }kjk fd;k tkrk gS&
When Fe 2 O 3 and SiO 2 both are present in Alumina as impurities then ................
method is applied for its purification?
8 'kr~ izfr'kr 'kq) ,Y;wehfu;e izkIr djus gsrq ,Y;wehfu;e dk 'kks/ku --------fof/k
}kjk fd;k tkrk gSA
For getting 100 percent pure aluminium metal purification is done by ........
method?
9 'kq) ,Y;wehuk dk xyukad cgqr Åapk ¼yxHkx 2050°C½ gksrk gSA bls de
rki ij fi?kykus dh –f"V ls blesa ---------------- ,oa ---------------- xkyd ds :i esa
iz;qDr fd;s tkus ls xyukad ------------°C ij gh vk tkrk gSA
Pure Alumina is melted at very high temperature (approximately 2050°C).
To melt ii at low temperature ................... and ................ are mixed as flux
which reduce melting point upto ............°C.
10 tc flfydk dh v'kqf) ckDlkbV esa vf/kd gks rc bl [kfut dk 'kks/ku
----------------- fof/k }kjk fd;k tkrk gSA bl fof/k esa --------------- feykdj N dh 2
/kkjk esa 1800°C rd xeZ djrs gSaA
When SiO 2 is present as main impurity in boxite then it is purified by the
method .................. In this method ............... is mixed and is heated in presence
of N 2 at about 1800°C.
11 flfydk ;qDr v'kqf) okys ckDlkbV [kfut dks N dh /kkjk esa dkWd ds lkFk
2
1800°C ij xeZ djus ls ---------------- izkIr gksrk gS rFkk flfydkWu ok"i'khy
gksus ls vyx gks tkrk gSA
69