Arock sample weighing 5.88 x 10-4 g is known to contain calcium, phosphorus, and oxygen. the amount of the first two elements in this rock is found to be 2.28 x 10-4 g and 1.18 x 10-4 g respectively. what is the empirical formula for the compound in this rock sample?

Ca₃P₂O₈.

Explanation:

The mass of oxygen in the rock = the mass of the rock - (the mass of Ca + the mass of P) = (5.88 x 10⁻⁴ g) - (2.28 x 10⁻⁴ g + 1.18 x 10⁻⁴ g) = 2.42 x 10⁻⁴ g.

no. of moles = mass/atomic mass.

no. of moles of Ca = (2.28 x 10⁻⁴ g)/(40.078 g/mol) = 5.689 x 10⁻⁶ mol.

no. of moles of P = (1.18 x 10⁻⁴ g)/(30.97 g/mol) = 3.81 x 10⁻⁶ mol.

no. of moles of O = (2.42 x 10⁻⁴ g)/(16.0 g/mol) = 1.51 x 10⁻⁵ mol.

The mole ratio of (Ca: P: O) will be ((5.689 x 10⁻⁶ mol)/(3.81 x 10⁻⁶ mol): (3.81 x 10⁻⁶ mol)/(3.81 x 10⁻⁶ mol): (1.51 x 10⁻⁵ mol)/(3.81 x 10⁻⁶ mol)).

∴ The mole ratio of (Ca: P: O) will be (1.5: 1.0: 4.0).

Multiplying by 2.0 to get the empirical formula of the rock:

The empirical formula of the rock is Ca₃P₂O₈.

< > according to newton's third law of motion, forces always act in equal but opposite pairs. another way of saying this is for every action, there is an equal but opposite reaction.< >

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.