(i) The temperature of a reaction increases, the adding heat provides energy to break more bonds of the reactant molecules.
(ii) So more reactants ions increases, produce more products.
(iii) Thus speed of the reaction increases.

Hind brain is formed of three parts (1) cerebellum, (2) pons and (3) medulla oblongata.

RBCs are biconcave and disc - shaped.

(i) A solution must at least be consisting of two components ( a solute and a solvent ).
(ii) Such solution which are made of one solute and one solvent (two components) are called binary solution.
(iii) e.g: On addition copper sulphate crystals to water.

Respiration takes place through skin.

When xylem lies towards the centre and phloem lies towards the periphery, it is called collateral vascular bundle.

Radium.

(i) Resistance is inversely proportional to area of cross section. \(\mathbf{R} \alpha \frac{l}{A}\)
(ii) A thicker wire has Iarger area of cross section and hence the resistance decreases.

If the particles of the medium vibrate along the direction of propagation of the wave, then the waves are said to be longitudinal.

Isotopes of oxygen and its percentage abundance

(i) The ratio of increase in volume of the body per degree rise in temperature to its unit volume is called as co-efficient of cubical expansion.
(ii) SI unit is K^-1.
(iii) Co - efficient of cubical expansion can be expressed as \(\frac{\Delta V}{V_{o}}=\alpha_{v} \Delta T\)

Snell's law state that, the ratio of the sine of the angle of incidence and sine of the angle of refraction is equal to the ratio of refractive indices of the two media.
\(\frac{\sin i}{\sin r}=\frac{\mu_2}{\mu_1}\)

Based on the direction in which the force acts, they can be classified into two types as:
(i) Like Parallel forces
(ii) Unlike Parallel forces.

(i) A - reddish brown metal - Copper
(ii) When copper is heated at < 1370 K in the presence of oxygen, copper forms black colour Copper (II) oxide (CuO).
(iii) \(2 \mathrm{Cu}+\mathrm{O}_{2} \stackrel{\text { below } 1370 \mathrm{~K}}{\longrightarrow} \underset{\text { (copper (Il)oxide-black) }}{2 \mathrm{CuO}}\)
(iv) When copper is heated at >1370 K in the presence of oxygen, copper forms red colour Cop-per (I) oxide \((\mathrm{Cu}_{2} \mathrm{O} )\)
(v) \(4 \mathrm{Cu}+\mathrm{O}_{2} \stackrel{\text { above } 1370 \mathrm{~K}}{\longrightarrow} \underset{\text { (copper-I-oxide-red) }}{2 \mathrm{Cu_2O}}\)
(vi) A - copper (Cu)
(vii) B - copper (II) oxide (CuO) - Black coloured
(viii) \(\mathbf{C} - copper-I-oxide \left(\mathrm{Cu}_{2} \mathbf{O}\right)-\operatorname{Red}\) coloured