41. Which of the following methods is used to estimate hydrogen in an organic compound ?
A. Combustion method
B. Dumas method
C. Kjeldahls method
D. All of the above methods are for different purposes
42. The nucleus of an atom of every element will always contain____________________?
B. protons and electrons
D. protons and neutrons
43. When 0.5 mole of phosphoric acid is dissolved in aqueous solution how many moles of -ve and +ve ions are collected altogether ?
44. Dempsters mass spectrometer has number of zones / parts_________________?
45. All the following variables are used to describable gases except__________________?
46. The mass of deci mole of electrons (NA) is___________________?
A. 1.008 mg
B. 0.184 mg
C. 0.054 mg
D. 5.4 mg
47. Which of the following statements is wrong about isotopes ?
A. they possess different mass number
B. they possess different physical properties
C. they possess same chemical properties
D. they possess different position in the periodic table
48. Qualitative analysis is carried out for _________________?
A. identification of elements
B. estimation of amounts of elements
C. molar ration of elements
D. molar volume of elements
49. Combustion analysis is performed to determine__________________?
A. Empirical formula
B. Molecular mass
C. Molecular formula
D. Formula mass
50. Isotopes differ in_________________?
A. properties which depend upon mass
B. arrangement of electrons in orbitals
C. chemical properties
D. all of the above