For the process to occur under adiabatic conditions, the correct condition is:
(i) ΔT = 0
(ii) Δp = 0
(iii) q = 0
(iv) w = 0

Calculate the amount of carbon dioxide that could be produced when

(i) 1 mole of carbon is burnt in air.

(ii) 1 mole of carbon is burnt in 16 g of dioxygen.

(iii) 2 moles of carbon are burnt in 16 g of dioxygen.

A sample of drinking water was found to be severely contaminated with chloroform, CHCl₃, supposed to be carcinogenic in nature. The level of contamination was 15 ppm (by mass).

(i) Express this in percent by mass.

(ii) Determine the molality of chloroform in the water sample.

Determine the empirical formula of an oxide of iron which has 69.9% iron and 30.1% dioxygen by mass.

Write the general outer electronic configuration of s-, p-, d- and f- block elements.

In a reaction A + B2 → AB2 Identify the limiting reagent, if any, in the following reaction mixtures.

(i) 300 atoms of A + 200 molecules of B

(ii) 2 mol A + 3 mol B

(iii) 100 atoms of A + 100 molecules of B

(iv) 5 mol A + 2.5 mol B

(v) 2.5 mol A + 5 mol B

Calculate the wavelength, frequency and wave number of a light wave whose period is 2.0 × 10^–10 s.

Calculate the mass of sodium acetate (CH₃COONa) required to make 500 mL of 0.375 molar aqueous solution. Molar mass of sodium acetate is 82.0245 g mol^–1

Calculate the mass percent of different elements present in sodium sulphate (Na₂SO₄).

Calcium carbonate reacts with aqueous HCl to give CaCl₂ and CO₂ according to the reaction,

CaCO_3(s) + 2 HCl_(aq) → CaCl_2(aq) + CO_2(g) + H₂O_(l)

What mass of CaCO₃ is required to react completely with 25 mL of 0.75 M HCl?

A welding fuel gas contains carbon and hydrogen only. Burning a small sample of it in oxygen gives 3.38 g carbon dioxide, 0.690 g of water and no other products. A volume of 10.0 L (measured at STP) of this welding gas is found to weigh 11.6 g. Calculate

(i) empirical formula,

(ii) molar mass of the gas, and

(iii) molecular formula.

Isotope

Isotopic molar mass

Abundance

³⁶Ar

35.96755 gmol^–1

0.337%

³⁸Ar

37.96272 gmol–1

0.063%

⁴⁰Ar

39.9624 gmol^–1

99.600%

Use the data given in the following table to calculate the molar mass of naturally occurring argon isotopes:

Give one method for industrial preparation and one for laboratory preparation of CO and CO₂ each.

Calculate the wavelength, frequency and wave number of a light wave whose period is 2.0 × 10^–10 s.

Beryllium and magnesium do not give colour to flame whereas other alkaline earth metals do so. Why?

A certain particle carries 2.5 × 10^–16C of static electric charge. Calculate the number of electrons present in it.

Calculate the wavelength of an electron moving with a velocity of 2.05 × 10⁷ ms^–1.

Determine the empirical formula of an oxide of iron which has 69.9% iron and 30.1% dioxygen by mass.

The compound AgF₂ is an unstable compound. However, if formed, the compound acts as a very strong oxidizing agent. Why?

At 450K, K_p= 2.0 × 10¹⁰/bar for the given reaction at equilibrium.

2SO₂(g) + O₂(g) ↔ 2SO₃ (g)

What is K_c at this temperature ?

(i) Calculate the total number of electrons present in one mole of methane.

(ii) Find

(a) the total number and

(b) the total mass of neutrons in 7 mg of 14C. (Assume that mass of a neutron = 1.675 × 10–27 kg).

(iii) Find

(a) the total number and

(b) the total mass of protons in 34 mg of NH3 at STP.

Will the answer change if the temperature and pressure are changed?