A cation M and an anion N have the following composition:
M and N form a compound with formula M3N2. p, q, r and s are respectively ________.
A11, 12, 13, 28
B10, 11, 13, 27
C13, 11, 12, 25
D10, 11, 13, 28
i didnt get this ques how sodium will gain 3 electrons
During her summer vacations, Nishtha is going to a place where stilt houses and floods
are very common. Which of the following should she preferably pack in her luggage?
Refer to the given figures, P and Q.
How do reproductive cells produced in P differ from those produced in Q in terms of production and their modes of storage?
A Mature cells of P can get stored for longer periods in reproductive tract whereas in Q, only immature cells remain stored.
B P produces fewer reproductive cells than Q does.
C Reproductive cells produced by P do not show motility.
D Q produces reproductive cells for a longer period in an individual’s life span than P does.
Why is the switch for any electrical appliance in ac circuit always connected to the live wire?
A No current flows in the neutral wire.
B There will be a short circuit if the switch is in the Earth lead.
C The device can be switched off easily if the switch is in the neutral lead.
D The device can be isolated (mode safe) if the switch is in the live lead.
Which of the following is correct?
A Water can be used for extinguishing fires caused due to electrical faults.
B Carbon is a non-metal so it cannot be used in electrolytic cell.
C A liquid conducts electricity because of the presence of ions.
D Pure water forms ions to conduct electricity.
answer shall be c
A housewife was preparing hot meal for her family.
She accidentally placed her fingertip into some boiling
soup, but quickly withdrew it. She felt significant
pain in the finger immediately after that. Which of the
following is the most likely explanation for this time lag?
A The withdrawal of her finger is a reflex action that is triggered more quickly than the transmission of information related to pain stimulus to her brain.
B The pain receptors present on her finger skin are less efficient, so information regarding pain is transmitted to brain at a slower rate as compared to that of heat.
C The withdrawal of her finger is controlled by brain so it occurs very fast whereas feeling of pain is a reflex action controlled by spinal cord so it takes comparatively much more time.
D None of these
Seema took four syringes with stoppers inserted at their nozzles. Each syringe contains a different substance. All syringes are completely filled with their contents such that their plungers are pulled out to the maximum. Which of the following plungers can be pushed in easily?
Which of the following statement(s) is/are incorrect?
(i) Two thin woollen sweaters are warmer than a thick woollen sweater.
(ii) It saves fuel if we cook food in a vessel which is blackened at the bottom and polished from the sides.
(iii) The cable wires between two poles are left loose because in summers, the wires do not break on expanding.
A Only (i) and (iii)
B Only (ii) and (iii)
C Only (iii)
D Only (i)
How will leaving it loose relate to expansion in summers? Summer should be replaced with winters and expanding we replaced with contracting..