2 gm of aluminium is treated separately with excess of dil. H2SO4 and excess of NaOH, the ratio of volume of hydrogen evolved is :
1 : 1
2 : 3
1 : 2
2 : 1
The main component of glass which gives heat resistance to laboratory glassware is
PbO
MgO
B2O3
Al2O3
C.
B2O3
The main component of glass which gives heat resistance to laboratory glassware is B2O3.
The order of acidic strength of boron trihalides is :
BF3 < BCl3< BBr3 <BI3
BI3 < BBr3 < BCl3 < BF3
BCl3< BBr3 <BI3 < BF3
BBr3 <BI3 < BF3 < BCl3
Match list I and list II and select the correct answer using the code given below the lists :
List I Nuclear reactor components | List II substance |
1. Moderator | A.Uranium |
2. Control rods | B.Graphite |
3. Fuel rods | C.Boron |
4.Coolant | D.Lead |
E.Sodium |
1-B, 2-A, 3-C, 4-E
1-B, 2-C, 3-A, 4-E
1-E, 2-B, 3-A, 4-C
1-C, 2-D, 3-A, 4-B
The oxidation state shown by silicon when it combines with strongly electropositive metals is
-2
-4
+4
+2
Which one of the following is correct about stability of the given ions?
Pb2+ > Pb4+
Pb4+ > Pb2+
Si2+ > Si4+
Sn4+ > Sn2+