Matter is anything that has mass and occupies space.

The SI unit of mass is kilogram.

One mole of any substance always contains exactly 1 gram of that substance.

Atomic mass unit is defined as exactly one-twelfth the mass of a carbon-12 atom.

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

Relative atomic mass has no unit.

Avogadro number represents the number of atoms in exactly 12 g of carbon-12.

The empirical formula of a compound represents the actual number of atoms of each element in one molecule.

Density is defined as mass divided by volume.

If the molar mass of a compound is twice its empirical formula mass, the molecular formula is double the empirical formula.

The law of definite proportions states that a chemical compound always contains the same elements in the same mass ratio.

Mole fraction is always greater than one for the major component of a mixture.

For a balanced chemical equation, the number of atoms of each element must be equal on both sides.

Molar mass of a substance is numerically equal to its molecular mass but expressed in \(\mathrm{g\,mol^{-1}}\).

In a limiting reagent problem, the reactant present in excess determines the amount of product formed.

Percentage yield of a reaction can be greater than 100% if excess reactant is used.

The average atomic mass of an element depends on the isotopic composition of that element.

One mole of an ideal gas occupies 22.4 L at STP.

If 1 g of hydrogen reacts completely with oxygen, the mass of water formed must be greater than 1 g.

The number of significant figures in a measured quantity depends on the measuring instrument.

When two reactants are mixed in stoichiometric proportions, neither is left unreacted after completion.

In dimensional analysis, conversion factors are treated as exact numbers.

If the molar mass of a compound is an integral multiple of its empirical formula mass, that multiple must be an integer.

The law of multiple proportions applies only when two elements form exactly two compounds.

In a reaction, if the actual yield is much lower than the theoretical yield, side reactions and losses are possible causes.