Question

56 Grams Of Calcium Oxides Contains
A.60.23*10^23 Atoms Of Calcium Oxide B 0.6023*10^23Molecules Of Calcium Oxide
C 6.023*10^23 Molecules Of Calcium Oxide D 0.06023*10^23 Molecules Of Calcium Oxide

Answer 1

Answer:

56 Grams Of Calcium Oxides contains 6.023 × 10²³ Molecules Of Calcium Oxide

Explanation:

Avagadro's constant / Avogadro's number:

1 mole of any compound or element contains exactly 6.023 × 10²³ molecules of the compound or atoms of the element.

Let us calculate to find how many moles we have in 56 grams of Calcium oxide CaO

The molar mass of calcium is 40 and that of oxygen is 16, therefore the molar mass of CaO is 40 + 16 = 56g/mol

The next step is to calculate the moles of CaO:

               Moles  = mass/molar mass

                            = 56 grams / 56gmol⁻¹

                            = 1 mole

Therefore the moles of 56 grams of Calcium Oxide is 1 mole

According to Avogadro's number we know 1 mole of any compound, we have exaclty 6.023 × 10²³ molecules of that compound.

Therefore we have 6.023 × 10²³ molecules of CaO in 56g of Calcium Oxide.

Answer 2

56 Grams Of Calcium Oxides Contains

• (A) 60.23*10^23 Atoms Of Calcium Oxide.
• ( B) 0.6023*10^23Molecules Of Calcium Oxide.
• (C) 6.023*10^23 Molecules Of Calcium Oxide.
• (D) 0.06023*10^23 Molecules Of Calcium Oxide

answer : option (c) 6.023 × 10²³ molecules of calcium oxide

explanation : given, mass of calcium oxide = 56g

molar mass of calcium oxide, CaO = 40 + 16 = 56g/mol

so, number of moles of calcium oxide = given mass/molar mass = 56/56 = 1

hence, 56gram of calcium oxide contains 1 mol molecules.

but we know, from Avogadro's concept.

1 mol of molecules means 6.023 × 10²³ molecules.

so, 56gram of calcium oxide contains 6.023 × 10²³ molecules of it.