Biuret test is a chemical test used for detecting the presence of
- A. carbohydrates
- B. proteins
- C. amines
- D. alkanoates
The empirical formula of an organic liquid hydrocarbon is XY. If the relative molar masses of X and Y are 72 and 6 respectively, it’s vapour density is likely to be
- A. 33
- B. 66
- C. 39
- D. 78
An organic compound contains 53.1% Carbon, 6.2% Hydrogen, 12.4% Nitrogen, and 28.3% Oxygen by mass. What is the molecular formula of the compound if its vapour density is 56.5? [ C =12, H = 1, N = 14, O = 16].
- A. C\(_5\)H\(_7\)NO\(_2\)
- B. C\(_5\)H\(_6\)NO\(_2\)
- C. C\(_3\)H\(_6\)NO\(_2\)
- D. C\(_3\)H\(_7\)NO\(_2\)
A liquid hydrocarbon obtained from fractional distillation of coal tar that is used in the pharmaceutical industry is
- A. xylene
- B. benzene
- C. hexane
- D. Toluene
During the fractional distillation of crude oil, the fraction that distills at 200 – 250\(^0\) C is
- A. bitumen
- B. diesel
- C. kerosene
- D. petrol
The constituent of petroleum fraction used in surfacing road is
- A. petrol
- B. diesel
- C. lubricating oil
- D. bitumen
When Calcium ethynide is decomposed by water, the gas produced is
- A. CO
- B. H\(_2\)
- C. C\(_2\)H\(_2\)
- D. CH\(_4\)
In the extraction of Aluminium, the silica impurity is removed by
- A. electrolysis
- B. filtration
- C. reaction with H\(_2\)SO\(_4\)
- D. precipitation
Silver and Gold are metals found as free uncombined elements in the earth’s crust, which makes them to be referred to as
- A. corrosive metals
- B. reactive metals
- C. natural metals
- D. noble metals
The constituents of Alnico are Aluminium, Nickel and
- A. Mg
- B. Co
- C. Mn
- D. Cu
The number of molecules of helium gas contained in 11.5g of the gas is
- A. 1.73 x 10\(^{23}\)
- B. 1.73 x 10\(^{22}\)
- C. 1.73 x 10\(^{24}\)
- D. 1.73 x 10\(^{21}\)
At a given temperature and pressure, a gas X diffuses twice as fast as gas Y. It follows that
- A. Gas Y is two times as heavy as Gas X
- B. Gas Y is four times as heavy as Gas X
- C. Gas Y is monoatomic
- D. Gas X is diatomic
Which of the following is a common laboratory indicator for bases?
- A. Methyl orange
- B. Phenolphthalein
- C. Bromothymol blue
- D. Litmus
What is the maximum number of electrons that can occupy the second energy level (n=2)?
- A. 2 electrons
- B. 18 electrons
- C. 8 electrons
- D. 32 electrons
Which of the following statements is true for strong electrolytes?
- A. They do not conduct electricity in the molten state
- B. They completely dissociate into ions in solution
- C. They are non-polar substances
- D. They partially dissociate into ions in solution
An element has an atomic number of 8 and a mass number of 16. How many neutrons does this element have?
- A. 24
- B. 16
- C. 8
- D. 32
Which of the following statements is true regarding the melting and boiling points of pure substances?
- A. The boiling point is always higher than the melting point
- B. The melting point is always higher than the boiling point
- C. The melting and boiling points are always the same for all substances
- D. The melting and boiling points can vary depending on the substance
What is the IUPAC name for the compound CCl\(_4\)?
- A. Tetrahydrochloride
- B. Tetrachloromethane
- C. Carbon tetrachloride
- D. Chloroform
The lanthanides and actinides are located in which block of the periodic table?
- A. P-block
- B. S-block
- C. F-block
- D. D-block
Which of the following is a characteristic property of acids?
- A. Turn litmus paper blue
- B. Bitter taste
- C. pH value above 7
- D. React with metals to produce hydrogen gas
Which of the following is an example of a primary cell?
- A. Alkaline battery
- B. Nickel-cadmium battery
- C. Lead-acid battery
- D. Lithium-ion battery