You have four test tubes, A, B, C and D containing sodium carbonate, sodium chloride, lime water and blue litmus solutions respectively. Out of these the material of which test tube/ test tubes would be suitable for the correct test of acetic/ethanoic acid?

• only A

• A and B

• B and C

• B and C

• Mustard oil and calcium hydroxide

• Castor oil and calcium hydroxide

• Turpentine oil and sodium hydroxide

• Turpentine oil and sodium hydroxide

A student took four test tubes P, Q, R and S and filled about 8 mL of distilled water in each. After that he dissolved an equal amount of Na₂SO₄ in P, K₂SO₄ in Q, CaSO₄ in R and MgSO₄ in S. On adding an equal amount of soap solution and shaking each test tube well, a good amount of lather will be obtained in the test tubes,

• P and Q

• P and R

• P, Q and S

• P, Q and S

A student while observing an embryo of a gram seed listed various parts of the embryo as listed below :

Testa, Micropyle, Cotyledon, Tegmen, Plumule, Radicle. On examining the list the teacher commented that only three parts are correct. Select these three correct parts :

• Cotyledon, Testa, Plumule

• Cotyledon, Plumule, Radicle

• Cotyledon, Tegmen, Radicle

• Cotyledon, Tegmen, Radicle

Select the set of homologous organs from the following:

• Wings of pigeon and a butterfly

• Wings of bat and a pigeon

• Forelimbs of cow, a duck and a lizard

• Forelimbs of cow, a duck and a lizard

Three students A, B and C focussed a distant building on a screen with the help of a concave mirror. To determine focal length of the concave mirror they measured the distances as given below:
Student A : From mirror to the screen
Student B : From building to the screen
Student C : From building to the mirror
Who measured the focal length correctly

• Only A
• Only B
• A and B
• A and B

If you focus the image of a distant object, whose shape is given
below, on a screen using a convex lens,

the shape of the image of this object on the screen would be:

In the following diagram the correctly marked angles are:

• ∠ A and ∠ e

• ∠ i, ∠ A and ∠ D

• ∠ A, ∠ r and ∠ e

• ∠ A, ∠ r and ∠ e

The correct sequencing of the angle of incidence, the angle of emergence, the angle of refraction and lateral displacement shown in the following diagram by digits 1, 2, 3 and 4 is:

• 2, 4, 1, 3

• 2, 1, 4, 3

• 1, 2, 4, 3

• 1, 2, 4, 3

Write the molecular formula of first two members of homologous series having functional group –Cl.