Observe the given figure carefully.
Which of the following statements is correct?
AThe changes taking place can easily be reversed.
BGas X is oxygen.
CTest tube will be warmer after the change as this change is exothermic.
DNone of these
If it is exothermic then heat escapes so test tube should be cool
A cricket ball of mass 150 g moving with a speed of 28. Match Column I with Column II and select the correct 126 km/h hits at the middle of the bat, held firmly at option from the codes given below. its position by the batsman. The ball moves straight Column I Column II back to the bowler after hitting the bat. Assuming that collision between ball and bat is completely elastic and the two remain in contact for 0.001 s, the force
that the batsman had to apply to hold the bat firmly at its place would be ________.
C1.05 × 104 N
D2.1 × 104 N
question is wrong
Garima performed an experiment to test the properties of four different objects and tabulated her results as follows.
Based on the above given information, which of the following best represents object W, X, Y and Z?
|A||Iron ball||Thermocol bead||Glass bead||Plastic ball|
|B||Glass bead||Plastic ball||Iron ball||Thermocol bead|
|C||Thermocol bead||Iron ball||Wooden bead||Glass bead|
|D||Rubber ball||Plastic ball||Thermocol bead||Iron ball|
The steps of wastewater treatment plant are given below randomly.
(i) Wastewater is passed into sedimentation tank.
(ii) Sludge is decomposed by anaerobic bacteria.
(iii) Wastewater is passed through bar screens.
(iv) Wastewater is passed to grit and sand removal tank.
(v) Solids settle at the bottom and floatable materials are removed by skimmer.
(vi) Aeration of water takes place.
(vii) Disinfection of water by adding chlorine.
Which of the following represents correct sequence of steps?
A (iii) → (iv) → (i) → (v) → (ii) → (vi) → (vii)
B (iv) → (iii) → (i) → (v) → (ii) → (vi) → (vii)
C (iii) → (iv) → (v) → (i) → (ii) → (vi) → (vii)
D (iii) → (iv) → (i) → (ii) → (v) → (vi) → (vii)
Which of the following is/are not the function(s) of the part labelled as X in the given figure ?
(i) To absorb water from the soil.
(ii) To transport food to all parts of the plant.
(iii) To transport water to all parts of the plant.
(iv) To hold the plant upright to receive sunlight.
C(i) and (ii)
D(ii), (iii) and (iv)
Refer to the given flow chart and identify animals P, Q and R.
Which of the following damages are associated with acid rain?
(i) Erosion of stone statues and buildings
(ii) Melting of ice caps
(iii) Increase in the number of mosquitoes
(iv) Threat to the life of aquatic beings
(v) Loss of soil fertility.
A(i), (ii) and (iii) only
B(i), (iv) and (v) only
C(i) and (iii) only
D(ii), (iii) and (v) only
In the solution, it says that the melting of ice caps is an incorrect option, but why? Acid rain is nothing but industrial chemicals that react with water vapour in the air and precipitate in form of hail, snow or rain and is acidic to nature. So in the poles, this acid can fall as snow, so they can melt the ice sheets, right? Please explain this question.