A fixed volume of water will dissolve a certain amount of salt. If the same volume of water is then heated, more salt can be made to dissolve in it. The best explanation to this is________.
AHeating increases the spaces between the water molecules
BHeating reduces the size of the salt particles
CSalt melts in hot water
DBoth water and salt particles become smaller when heated
During the process of inhalation in human beings _________.
(A) Diaphragm contracts but external intercoastal muscles and lungs expand.
(B) Diaphragm expands but external intercoastal muscles and lungs contract.
(C) Diaphragm and external intercoastal muscles expand but lungs contract.
(D) Diaphragm and external intercoastal muscles contract but lungs expand.
Which of the following statements are incorrect?
(i) Cellular respiration is a physical process in which food molecules are broken down into carbon dioxide and water.
(ii) Anaerobic respiration involves breakdown of glucose into alcohol and carbon dioxide.
(iii) Breathing rate varies according to oxygen requirement of the body.
(iv) On land, frogs breathe through lungs and in water by gills.
(v) Respiration in plants occurs through stomata and lenticels.
A(i), (ii) and (iv) only
B(i) and (iv) only
C(ii), (iii) and (v) only
D(ii), (iii) and (iv) only
i doubt on it . how could cellular respiration could be a physical one.
Study the given flow chart.
Which among P, Q, R and S could be Mars and Uranus respectively?
A P and R
B Q and S
C S and R
D S and Q
Two persons X and Y went to see a doctor for their respective diseases. The given box shows what they
communicated to the doctor about their illness.
Person X : “I have swollen gums that bleed when I brush my teeth or eat anything. My joints are also swollen and keep paining.”
Person Y : “I am unable to see properly in dim light.”
What can be concluded about these persons?
APerson X does not take citrus fruits in his diet.
BPerson Y is suffering from iron deficiency. So he should take lots of green leafy vegetables in his diet.
CPerson X is suffering from scurvy whereas person Y is suffering from rickets.
DBoth the persons are diseased due to deficiency of vitamins but person X is having vitamin A deficiency and person Y is having vitamin C deficiency.
Solve the given crossword and select the option which is not given in it.
A Easiest method to purify water at home.
B Gas given out by plants during photosynthesis.
C Major component of air.
D Insoluble impurities can be separated by this method.
no carbon dioxide neither nitrogen
Four different-sized beakers are filled with water up to the same height. The temperature of the water is same in all four beakers. If we put 100 gram of ice
in each beaker, what effect will occur?
A The temperature of water in beaker 2 will change the most.
B The ice will melt fastest in the beaker 3.
C The temperature changes will be same in all four beakers.
D The temperature of the water in beaker 3 will change the most.