How many moles of lead (II) chloride will be formed from a reaction between 6.5 g of PbO and 3.2 g of HCl?
0.044
0.333
0.011
0.011
An element, X has the following isotopic composition;
200X: 90%
199X : 8.0%
202X ; 2.0 %
The weighted average atomic mass of the naturally -occurring element X is closet to:
200 amu
201 amu
202 amu
202 amu
Work is being performed, when a weight lifter lifts a base ball off a weight rack. This is due to
magnetic attraction
gravity
electrostatic repulsion
mechanical force
For preparing 3.00 L of 1M NaOH by mixing portions of two stock solutions (A and B) of 2.50 M NaOH and 0.40 M NaOH respectively. Find out the amount of B stock solution (in L) added.
8.57 L
2.14 L
1.28 L
7.51 L
What would be the heat released when an aqueous solution containing 0.5 mole of HNO3 is mixed with 0.3 mole of OH-? (enthalpy of neutralisation is- 57.1 kJ)
28.5 kJ
17.1 kJ
45.7 kJ
1.7 kJ
The number average molar mass and mass average molar mass of a polymer are respectively 30,000 and 40,000. The
polydispersity index (PDI) of the polymer is
-1
0
> 1
< 1
0.001 mole of [Co(NH3)5(NO3) (SO4)] was passed through a cation exchanger and the acid coming out of it required 20mL of 0.1 M NaOH for neutralisation. Thus, the complex is
[Co(NH3)5(NO3)] SO4
[Co(NH3)5(SO4)]NO3
[Co(NH3)5] NO3.SO4
None of the above
A.
[Co(NH3)5(NO3)] SO4
Millimoles of acid required for neutralisation
= 20 x 0.1 = 2 millimoles
= 0.002 moles
If 0.001 mole is neutralising 0.002 moles of base, thus, 0.001 mole of base remains unreacted. Hence, acid coming out should be basic.
[Co(NH3)5(NO3)] SO4 [Co(NH3)5(NO3]2+ + SO2- 4.
In order to prepare one litre 1N solution of KMnO4, how many grams of KMnO4 are required, if the solution to be used in acid medium for oxidation?
128g
41.75 g
31.60 g
62.34 g
The osmotic pressure of blood is 8.21 atm at 37C. How much glucose would be used for an injection that is at the same osmotic pressure as blood?
22.17 gL-1
58.14 gL-1
61.26 gL-1
75.43 gL-1