Basics of Chemistry

In a chemical reaction , the heat is released, the reaction is called as

• endothermic reaction

• exothermic reaction

• exitthermic rxn

• entropy rxn

Which of the following chemical equation is wrong ?

• 2Mg + O₂——— > 2MgO

• Mg + O ——— > MgO

• 2Pb + O₂ ——— > 2PbO

• 2Ca+ O₂ ——— > 2CaO

Which of the following is correct valency of carbon?

• 2

• 3

• 5

• 4

Combustion is a reaction in which a substance reacts with

• hydrogen

• Nitrogen

• Oxygen

• Chlorine

What are the 3 particles that make-up the atom?

• protons, neutrons, and isotopes

• neutrons, isotopes, and electrons

• positives, negatives, and electrons

• protons, neutrons, and electrons