Front

What is the mass number of an isotope?

Back

The mass number of an isotope is the total number of protons and neutrons in its nucleus.

Front

What is the mole concept in chemistry?

Back

The mole is a unit that measures the amount of substance, defined as containing 6.022 x 10^23 entities (atoms, molecules, etc.).

Front

What is the difference between a physical change and a chemical change?

Back

A physical change is reversible and does not alter the substance's chemical composition, while a chemical change results in the formation of new substances.

Front

What are ionic compounds?

Back

Ionic compounds are formed from the electrostatic attraction between positively and negatively charged ions, typically resulting in high melting points and electrical conductivity when dissolved in water.

Front

What is a synthesis reaction?

Back

A synthesis reaction is a type of chemical reaction where two or more reactants combine to form a single product.

Front

What is the significance of the atomic number?

Back

The atomic number is the number of protons in the nucleus of an atom, which determines the element's identity.

Front

What is a chemical formula?

Back

A chemical formula is a representation of a substance using symbols for its constituent elements and numerical subscripts to indicate the number of atoms.

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; it is conserved.

Front

What is the difference between an endothermic and exothermic reaction?

Back

An endothermic reaction absorbs heat from the surroundings, while an exothermic reaction releases heat.

Front

What is a catalyst?

Back

A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process.