How many molecules of malic acid (C4H6O5), an acid found in apples and other fruits, are there in 1.25 g

5.61 * 10²¹ molecules

Explanation:

You have 1.25 g of malic acid, C4H.Os, an acid found in apples and other fruits. How many molecules of the acid do you have?

Solution:

A molecule is the group of two or more atoms held together by chemical bonds.

The number of molecules is calculated using the formula:

number of molecules in a substance = number of moles of substance * Avogadro constant

Avogadro constant = 6.02 * 10²³ mol⁻¹

number of moles = mass / molar mass

Given that mass = 1.25 g

molar mass of malic acid (C₄H₆O₅) = (12 * 4) + (1 * 6) + (16 * 5) = 48 + 6 + 80 = 134 g/mol

number of moles = mass / molar mass = 1.25 g / 134 g/mol = 0.0093 mol

Recall that: number of molecules in a substance = number of moles of substance * Avogadro constant

number of molecules in a substance = 0.0093 mol * 6.02 * 10²³ mol⁻¹ = 5.61 * 10²¹ molecules