NTSE SAT Chemistry Papers 12

At 283 K a saturated solution of solid X can be prepared by dissolving 21.0 g of it in 100 g of water. The maximum amount of X which can be dissolved in 100 g of water at 313 K is 62.0 g. An attempt is made to dissolve 50.0 g of X in 100 g of water at 313 K. A. All the 50.0 g of X will dissolve at 313 K B. At 313 K 29.0 g of X will remain undissolved C. Solubility of X decreases with increases of temperature D. On cooling the solution of X from 313 K to 283 K more than 21.0 g of X will crystallize out. Which of the above statements are correct?

Two elements A and B contain 13 and 8 protons respectively. If the number of neutrons in them happen to be 14 and 8 respectively; the formula unit mass for the compound between A and B unit would be:

The reaction of burning of carbon in oxygen is represented by the equation: \({{\text{C}}_{{\text{(s)}}}}{\text{ + }}\,{{\text{O}}_{{\text{2(g)}}}} \to {\text{C}}{{\text{O}}_{{\text{2(g)}}}}{\text{ + }}\,{\text{Heat + }}\,{\text{Light}}\) When 9.0 g of solid carbon in burnt in 16.0 g of oxygen gas, 22.0 g of carbon dioxide is produced. The mass of carbon dioxide gas formed on burning of 3.0 g of carbon in 32.0 g of oxygen would be (Note : atomic mass of C=12.0 u, O=16.0 u)

An atom of an element (X) has its K, L and M shells filled with some electrons. It reacts with sodium metal to form a compound NaX. The number of electrons in the M shell of the atom (X) will be

Oxygen gas reacts with hydrogen to produce water. The reaction is represented by the equation: \({O_2}(g) + {H_2}(g) \to {H_2}O(g)\) The above reaction is an example of A. Oxidation of hydrogen B. Reduction of oxygen C. Reduction of hydrogen D. Redox reaction

Match the items of Column I with the items of Column II

Which of the following represents the correct order of the acidic strength for equimolar aqueous solutions of HCI, \({H_2}S{O_4},N{H_4}OH\) and NaOH

Metals like sodium, potassium, calcium and magnesium are extracted by electrolysis of their chlorides in molten state. These metals are not extracted by reduction of their oxides with carbon because A. Reduction with carbon is very expensive B. Carbon readily makes alloys with these metals C. Carbon has less affinity for oxygen than these metals D. Carbon is a weaker reducing agent than these metals

A hydrocarbon has a molecular formula as \({C_6}{H_{12}}\). It does not react with hydrogen to give \({C_6}{H_{14}}\) nor does it react with chlorine to give \({C_6}{H_{12}}C{l_2}\). The hydrocarbon \({C_6}{H_{12}}\) is A. A saturated hydrocarbon B. An unsaturated hydrocarbon C. An open chain hydrocarbon D. A cyclo-alkane

An element with atomic number 17 is placed in the group 17 of the long form periodic table. Element with atomic number 9 is placed above it. Element with atomic number 16 is placed left and with atomic number 18 is placed right to it. Which of the following statements are correct? A. Valency of the element with atomic number 18 is zero B. Elements with same valency will have atomic number 16, 17 and 18 C. Valency of elements with atomic number 9, 17 and 35 is one D. Element with atomic number 17 is more electronegative than element with atomic numbers 16 and 35.

An organic compound is a clear liquid having a molecular formula \({C_4}{H_8}O\). It has an open chain structure. Without any carbon-carbon double bond. The compound can be A. An alcohol B. An ester C. An aldehyde D. A ketone

What happens when a fixed amount of oxygen gas is taken in a cylinder and compressed at constant temperature? (i) Number of collision of oxygen molecules at per unit area of the wall of the cylinder increase (ii) Oxygen \(\left( {{O_2}} \right)\) gets converted into ozone \(\left( {{O_3}} \right)\) (iii) Kinetic energy of the molecules of oxygen gas increases

The solubility of a substance S in water is 28.6% (mass by volume) at \(50^\circ C\) . When 50 ml of its saturated solution at \(50^\circ C\) is cooled to \(40^\circ C\), 2.4 g of solid S separated out. The solubility of S in water at \(40^\circ C\)(mass by volume) is:

What mass of \(C{O_2}\) will be formed when 6 g of carbon is burnt in 32 g of oxygen?

The law of conservation of mass is valid for which of the following? 1) Reactions involving oxidation 2) Nuclear reactions 3) Endothermic reaction