Which one of the following is a chemical change:
evaporation of spirit
freezing of water
heating of copper and sulphur
mixing of H2 and O2.
C.
heating of copper and sulphur
Which one of the following is a chemical change :
Which one of the following is a chemical change:
evaporation of spirit
freezing of water
heating of copper and sulphur
mixing of H2 and O2.
C.
heating of copper and sulphur
Which one of the following is a chemical change :
Write the steps you would use for making tea. Use the words—solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue.
Pragya tested the solubility of three different substances at different temperatures and collected the data as given below (results are given in the following table, as grams of substance dissolved in 100 grams of water to form a saturated solution).
Substance Dissolved |
Temperature in K |
||||
283 |
293 |
313 |
333 |
353 |
|
Potassium nitrate |
21 |
32 |
62 |
106 |
107 |
Sodium chloride |
36 |
36 |
36 |
37 |
37 |
Potassium chloride |
35 |
35 |
40 |
46 |
54 |
Ammonium chloride |
24 |
37 |
41 |
55 |
66 |
Pragya makes a saturated solution of potassium chloride in water at 353 K and leaves the solution to cool at room temperature. What would she observe as the solution cools? Explain.
Substance Dissolved |
Temperature in K |
||||
283 |
293 |
313 |
333 |
353 |
|
Potassium nitrate |
21 |
32 |
62 |
106 |
107 |
Sodium chloride |
36 |
36 |
36 |
37 |
37 |
Potassium chloride |
35 |
35 |
40 |
46 |
54 |
Ammonium chloride |
24 |
37 |
41 |
55 |
66 |
Find the solubility of each salt at 293 K. Which salt has the highest solubility at this temperature?
Substance Dissolved |
Temperature in K |
||||
283 |
293 |
313 |
333 |
353 |
|
Potassium nitrate |
21 |
32 |
62 |
106 |
107 |
Sodium chloride |
36 |
36 |
36 |
37 |
37 |
Potassium chloride |
35 |
35 |
40 |
46 |
54 |
Ammonium chloride |
24 |
37 |
41 |
55 |
66 |
Pragya tested the solubility of three different substances at different temperatures and collected the data as given below (results are given in the following table, as grams of substance dissolved in 100 grams of water to form a saturated solution).
Substance Dissolved |
Temperature in K |
||||
283 |
293 |
313 |
333 |
353 |
|
Potassium nitrate |
21 |
32 |
62 |
106 |
107 |
Sodium chloride |
36 |
36 |
36 |
37 |
37 |
Potassium chloride |
35 |
35 |
40 |
46 |
54 |
Ammonium chloride |
24 |
37 |
41 |
55 |
66 |
Mock Test Series