P
Q
R
R
Study the following figure in which a student has marked the angle of incidence (<i), angle of refrcation (< r), angle of emergence (< e), angle of prism ( < A) and the angle of deviation (<D). The corrected angles are:
Which of the following sets of materials can be used for conducting a saponification reaction for the preparation of soap?
Ca(OH)2 and neem oil
NaOH and neem oil
NaOH and mineral oil.
NaOH and mineral oil.
A student takes four test tubes marked P, Q, R and S of 25 mL capacity and fills 10 mL of distilled water in each. He dissolves one spoon full of four different salts in each as − KCl in P, NaCl in Q, CaCl2 in R and MgCl2 in S . He then adds 2 ml of a sample of soap solution to each of the above test tubes. On shaking the contents of each of the test tubes, he is likely to observe a good amount of lather (Foam) in the test tubes marked.
P and Q
R and S
P, Q and R
P, Q and R
Consider the following comments about saponification reactions;
I. Heat is evolves in these reactions.
II. For quick precipitation of soap, sodium chloride is added to the reaction mixtures.
III. Saponification reactions are a special kind of neutralization reactions.
IV. Soaps are basic salts of long-chain fatty acids
I, II and III
II, III and IV
I, II and IV
I, II and IV
A student has to perform the experiment " To identify the different parts of an embryo of an embryo of a dicot seed. "
Pea, gram, wheat
Red kidney bean, maize, gram
Maize, wheat, red kidney bean
Maize, wheat, red kidney bean
Which of the following is a correct set of homologous organs?
Forelimbs of a frog, bird and lizard
Spine of cactus and thorn of Bougainvillea
Wings of bat and wings butterfly
Wings of bat and wings butterfly
A.
Forelimbs of a frog, bird and lizard