Is Matter Around Us Pure
If action is always equal to the reaction, explain how a horse can pull a cart.
The horse pulls the cart with a force (action) in the forward direction. The cart also pulls the horse with an equal force (reaction) in the backward direction. This way, the two forces get balanced. The horse pushes the ground with its feet in the backward direction, while pulling the cart. So, the reaction of earth makes it move in the forward direction alongwith the cart.
Sponsor Area
Which separation techniques will you apply for the separation of the following?
Different pigments from an extract of flower petals.
Which separation techniques will you apply for the separation of the following?
Butter from curd.
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 |
Sponsor Area
Sponsor Area