Select the correct statements from the following:

A. Atoms of all elements are composed of two fundamental particles. B. The mass of the electron is $9.10939 \times 10^{-31}$ kg. C. All the isotopes of a given element show the same chemical properties. D. Protons and electrons are collectively known as nucleons. E. Dalton's atomic theory regarded the atom as an ultimate particle of matter.

Choose the correct answer from the options given below:

At S.T.P. the density of $\text{CCl}_4$ vapour in $\text{g/L}$ will be nearest to:

Calculate the mass of 95% pure $CaCO_3$ that will be required to neutralize 50 mL of 0.5 M HCl solution according to the following reaction: $$ CaCO_3(s) + 2HCl(aq) \rightarrow CaCl_2(aq) + CO_2(g) + 2H_2O(l) $$ [Calculate up to the second place of decimal point]

The molar mass of a compound (X), whose $2.6 \text{ mol}$ weighs $312 \text{ g}$, is:

Calculate the mole fraction of the solute in a $1.00 \text{ m}$ aqueous solution.

A compound X contains 32% of A, 20% of B and remaining percentage of C. Then, the empirical formula of X is: (Given atomic mass of A = 64; B = 40; C = 32 u)

When $50\text{ mL}$ of a $16.9\%\text{ (w/v)}$ solution of $\text{AgNO}_3$ is mixed with $50\text{ mL}$ of $5.8\%\text{ (w/v) NaCl}$ solution, then the mass of precipitate formed is: ($\text{Ag} = 107.8$, $\text{N} = 14$, $\text{O} = 16$, $\text{Na} = 23$, $\text{Cl} = 35.5$)

The density of a $2 \text{ M}$ aqueous solution of $NaOH$ is $1.28 \text{ g/cm}^3$. The molality of the solution is: [molecular mass of $NaOH = 40 \text{ g mol}^{-1}$]

How many moles of lead (II) chloride will be formed from a reaction between $6.5\text{ g}$ of $\text{PbO}$ and $3.2\text{ g}$ of $\text{HCl}$?