(a) State Joules law of heating and write its mathematical expression.

(b) Two resistors of resistances 2 Ω and 4 Ω are connected in

1. series
2. parallel

with a battery of given potential difference. Compute the ratio of total quantity of heat produced in the combination in the two cases if the total voltage and time are kept the same for both.

$\text{1.} \space \boxed{\text{A}} + \text{H}$2\text{O} \xrightarrow{\text{ELECTROLYSIS}} \underset{\text{CAUSTIC SODA}}{\boxed{\text{x}}} + \underset{\text{ANODE}}{\boxed{\text{Y} \uparrow}} + \underset{\text{CATHODE}}{\boxed{\text{Z} \uparrow}} \\[1em] \text{2.} \space \underset{\text{MOLTEN}}{\boxed{\text{A}}} \xrightarrow{\text{ELECTROLYSIS}} \underset{\text{CATHODE}}{\boxed{\text{M}}} + \underset{\text{ANODE}}{\boxed{\text{Y} \uparrow}} \\[1em] \text{3.} \space \boxed{\text{M}} + \text{CH}3\text{COOH} \longrightarrow \boxed{\text{P}} + \boxed{\text{Z} \uparrow} \\[1em] \text{4.} \space \text{CH}3\text{COOH} + \boxed{\text{Q}} \xrightarrow[\text{H}2\text{SO}_4]{\text{Conc.}} \boxed{\text{R}} \\[1em] \text{5.} \space \boxed{\text{R}} + \boxed{\text{X}} \longrightarrow \boxed{\text{P}} + \boxed{\text{Q}}

(a) Derive the names of A, Y, Z, M, P & R

Attempt either subpart B or C.

(b) Improvise an activity to test Z.

OR

(c) Name the process in which compounds X, Y & Z are formed from A. Justify your response.

Mohan and Rohit observed that shoots of a plant growing in shade bend towards the sunlight. Whereas, leaves of ‘Touch me not’ plant fold and droop soon after touching. They were curious to know how these movements occur in plants.

In order to help them understand the movements in the plants, answer the following questions:

Attempt either subpart A or B.

(a) What causes the bending of shoots in the plants as shown in figure A?

OR

(b) What causes the folding of the leaves in ‘Touch me not’ plant as shown in figure B?

(c) Compare the movement of growth of the pollen tube towards ovule with the movements shown in part A of the above figure.

(d) Compare the movement shown in figure B with the movement of body parts in the animals.

During a field trip, Mohan and Rohit observed that shoots of sunflower plants bend towards the sunlight. Whereas, leaves of ‘Touch me not’ plant begin to fold and droop soon after touching even during the day. They were curious to know how these movements occur in plants.

Attempt either subpart A or B.

(a) What causes the bending of shoots in the sunflower plants towards sunlight?

OR

(b) What causes the folding of the leaves in ‘Touch me not’ plants when touched by hand?

(c) Compare the movement of growth of the pollen tube towards ovule with the bending of shoots of sunflower plant towards sunlight.

(d) Compare the movement in folding of leaves of ‘Touch me not’ plants with the movement of body parts in the animals.