51. The unit \(JPa^{-1}\) is equivalent to
A. \(m^{3}\)
B. \(cm^{3}\)
C. \(dm^{3}\)
D. None of these
Answer : Option A
Explanation :
\(\frac{J}{Pa}=\frac{Work}{Pressure}=\frac{Nm}{Nm^{-2}}=m^{3}\)
52. The density of Al metal is 2.7 \(gcm^{-3}\). An irregularly shaped piece of aluminium weighing 40.0g is added to a 100mL graduated cylinder containing 50.0mL of water. upto what height the water level will rise in the cylinder ?
A. 14.8mL
B. 79.6mL
C. 64.8mL
D. 50mL
Answer : Option C
Explanation :
→ \(d=\frac{m}{v}\)
→ \(\therefore v=\frac{m}{d}\)
\( v=\frac{40}{2.7}\)
\(=14.8\ cm^{3}\)
→ Water level in cylinder = 50+ 14.8 = 64.8 mL
53. A sample of clay after drying partially was found to contain 50% silica and 7% water.The original sample of clay had 12% water, What is the percentage of silica in the original sample?
54. In which of the following pairs percent composition of element is not same ?
A. Benzene and ethyne
B. But - 2 - ene and Cyclobutane
C. Glucose and fructose
D. Phenol and ethanol
Answer : Option D
55. What weight of CuO will be required to provide 200Kg copper
Choose the proper option after studying following statement (T = True, F = False)
1. The percent composition of vinyl chloride and its polymer PVC are same.
2. The perecent compostion of phosphorous trioxide \((P_{2}O_{3})\) is half than that of its dimer phosphoroushexoxide \((P_{4}O_{6})\) for each of the elements present in them.
57. Impure sample of ZnS contains 42.34% Zn. What is the percentage of pure ZnS in the smaple ?
58. If the atomic mass of carbon were set at 50 amu, what would be the value of Avogadro’s number ?
A. \(5.01\times 10^{24}\)
B. \(6.022\times 10^{23}\)
C. \(1.66\times 10^{24}\)
D. None of these
Answer : Option B
59. For which of the following compounds molecular weigh cannot be determined from atomic weights ?
A. \(Fe_{4}\left [ Fe(CN)_{6} \right ]\)
B. \(TiO_{2}\)
C. \(TiO_{1.12}\)
D. None of these
Answer : Option D
60. Which one of the following contains greatest number of oxygen atoms ?
A. 1.0 g of O atoms
B. 1.0 g of \(O_{2}\)
C. 1.0 g of \(O_{3}\)
D. All have same number of atoms
Answer : Option D