Skip to content 1 Metal M, with two electrons in its valence shell (M shell), reacts with oxygen to form a compound that is slightly soluble in water.
SA (Short)
2 Find the molecular mass of nitric acid (HNO3).
SA (Short)
3 Find the molecular mass of methane (CH₄).
SA (Short)
4 An element X has six electrons in its outer shell and forms a diatomic molecule.
LA (Long)
5 You want to design a new ionic compound, where the total positive charge is 6+ and the total negative charge is 6-.
MCQ (Multiple Choice)
6 Find the formula unit mass of magnesium hydroxide, Mg(OH)₂.
SA (Short)
7 Find the formula unit mass of potassium chloride (KCl).
SA (Short)
8 A particular element (X) has one electron in its third shell.
LA (Long)
9 Write the chemical formulae for the following compounds.
SA (Short)
10 Choose the correct statement(s) and correct the false statement(s).
SA (Short)
11 Write the formulae of the compounds formed from the following pairs of ions.
SA (Short)
12 Determine the formula unit mass of the following substances.
SA (Short)
13 Which of the following, in the given figure, correctly represents Cl⁻ ion (Atomic number of chlorine = 17).
MCQ (Multiple Choice)
14 Write the formulae for the compounds formed by the reaction of:
SA (Short)
15 If a species has 11 protons, 12 neutrons and 10 electrons then:
SA (Short)
16 Two elements, P and Q, have the following configurations: P: 2, 8, 5 Q: 2, 8, 7
SA (Short)
17 Complete the table given below by writing the formulae of the compounds formed by the cations on the left and the anions at the top.
SA (Short)
18 5.3 g of sodium carbonate and 6.0 g of acetic acid react to produce 2.2 g of carbon dioxide, 0.9 g of water, and 8.2 g of sodium acetate. Verify whether the law of conservation of…
SA (Short)
19 Assertion (A): Copper sulphate conducts electricity in the molten state but not in the solid state.
AR (Assertion & Reason)
20 The species ²⁷Al, ⁸⁰Br⁻ and ²⁰¹Hg²⁺ have 13, 35 and 80 protons, respectively.
SA (Short)
21 You are given a chemical reaction in which zinc reacts with dilute hydrochloric acid to form zinc chloride and hydrogen gas.
LA (Long)
22 A student burns 10 g of ethanol in an open beaker.
SA (Short)
23 When 20 g of hydrogen reacts completely with 160 g of oxygen, how much water is formed according to the Law of Conservation of Mass?
SA (Short)
24 A compound consists of 40% sulfur and 60% oxygen by mass.
SA (Short)
25 Carbon monoxide (CO) contains carbon and oxygen in the mass ratio of 3 : 4.
SA (Short)
26 The Law of Definite Proportions holds true for compounds but not for mixtures.
SA (Short)
27 Students X and Y, both prepared an oxide of copper by combining copper and oxygen in the ratios of 4 : 1 and 8 : 2, respectively.
SA (Short)
28 Nitrogen has five valence electrons.
SA (Short)
29 The atomic number of fluorine is 9.
SA (Short)
30 Assertion (A): 2 g of hydrogen combines with 16 g of oxygen to form 18 g of water.
AR (Assertion & Reason)