Question

Find the weight of phosphorus in P4O10 containing 6 × 10^23 oxygen atoms

Answer 1

Answer:

28.2 g

Explanation:

Let us first calculate the weight of P4O10

mass of phosphorus is 31 g

and mass of oxygen is 16

Mass of P4O10 will be 4*31+10*16=284 g

Basic concept

one mole = molecular mass of compounds = Avogadro number of electron

So 284 g of P4O10 has 6.022*10^23 moles of P4O10

one mole of P4O10 contains 6 atom of oxygen

or 284 g contains 10*6.022*10^23 atoms of oxygen

so 6*10^23 g of oxygen will be in

$\frac{284*6*10^{23}}{10*6.022*10^{23} } = 28.2 g$

Answer 2

Answer:

28.29 grams

Explanation:

The chemical formula is: P₄O₁₀

We can see from the formula that 1 molecule of P₄O₁₀ contains 10 atoms of oxygen

In other words, 10 atoms of oxygen are contained in 1 molecule of  P₄O₁₀

⇒  6 x 10²³ oxygen atoms will be contained in (1/10) x 6 x 10 ²³ molecules of  P₄O₁₀

= 6 x 10²² molecules of  P₄O₁₀

Now, we need to find the mass of 6 x 10²² molecules of  P₄O₁₀.

By definition of moles, one mole = 6.022 x 10²³ entities

Mass of one mole of any substance = molar mass

Hence, by combining the above two definitions we can conclude

Mass of 6.022 x 10²³  molecules of  P₄O₁₀ = 284 g

Mass of  6 x 10²² molecules of  P₄O₁₀ = (284/ 6.022 x 10²³) x 6 x 10²²

                                                             = 28.29 grams