Can anyone solve and give 21 to 27 plss I will mark as brainliest plss
Answers
21)
1)CR2(so4)3
2)Pb(No3)2
B)
1)Al
2)neutrons=14 protons=13
3)EC-2,8,3
22)relative density is the density of a fluid in comparison to water
this is to reduce the pressure that is applied on the ground when the train passes over the tracks
23)the speed of sound varies with the change in medium
it increase when moved to a denser medium and vice versa
24)1)because it produces heat
2)it is irreversible
3)it forms a new compound(MgO)
25)it is because alum when dissolved in water forms a true solution,therefore it does not scatter light,hence the path of light is not seen.it also when salt or sugar is dissolved in water
27)Adjust the mirror of the microscope so that maximum light is available to illuminate the slide
take care to place the cheek cells in an isotonic solution
hope this helps you
plz mark it as brainliest