Class 11th

$Be{\left(OH\right)}_2$ is amphoteric in nature

$Be{\left(OH\right)}_2+2O{H}^{-}\to {\left. [Be{\left(OH\right)}_4\right]}^{2-}$

Generally, $?iH$ decreases down the group but Pb has higher $?iH$  than Sn due to poor shielding effect of intervening d and f orbitals.

Given beat frequency

$\left|X-95\right|=5$

$and\left|3X-290\right|=10$

$?X=100Hz$

Sulphuric acid, because of its low volatility can be used to manufacture more volatile acids from their corresponding salts.

^{$2MX+H_{2}S{O}_4\to 2HX+M_{2}S{O}_4\left(X=F,Cl,N{O}_3\right)$}

The desirable properties for handling a cooking pan is low thermal conductivity and high specific heat as it needs to quickly transmit heat and retain more heat for a given rise in temperature.

From Wien's displacement law.

${\lambda }_{m}T=b?T=\frac{2.89*{10}^{-3}}{2.5*{10}^{-6}}1.156*{10}^3$

$=1156K$

Kinetic energy $E?T$

$\frac{E_1}{E_2}=\frac{T_1}{T_2}$

$T_2=2*293$

$T_2=586K={313}^{0}C$

$COP=\frac{Q_t}{W}=\frac{T_{low}}{T_{high}-T_{low}}=\frac{250}{300-250}=5$

$\frac{Q_L}{W}=5$

$W=\frac{500*4.2}{5}420J$

Elongation in the wire is given as

$?I=\frac{Fl}{AY}$

$T_{max}=\frac{m{v}^2}{l}+mg$

$T_{max}=3mg$

$?l_{max}=\frac{3mgl}{\pi r^{2}Y}$