Question

The total number of neutrons present in 10g D2O (D is H) are :
(1) 2.5
(2) 5.0
(3) 10.0
(4) None of these

Answer 1

Answer: option c

Explanation:molar mass =20

and given mass to us is 10

mole is 0.5

as in

one mole of D2O number of neutron is = 10 x 6.022 x 10^23 or 10 mole

in 0.5 mole of D2O number of neutron is = 5 x 6.022 x 10^23 or 5 moles

it is easy to understand please mark as brainliest

Answer 2

Given,

The mass of D₂O = 10g

To Find,

The total number of neutrons in 10g of D₂O.

Solution,

• D₂O is a compound made of deuterium and oxygen.
• The difference between the mass and atomic numbers indicates the number of neutrons in an atom.
• Deuterium is an isotope of hydrogen.
• Deuterium, ₁D², has a mass number of 2 and atomic number 1.
• Thus the number of neutrons in each deuterium atom = $2-1 = 1$
• Oxygen, ₈O¹⁶, has an atomic number 8 and mass number 16.
• Thus the number of neutrons in oxygen = $16-8 = 8$
• The total number of neutrons in the D₂O molecule = $Number of neutrons in Deuterium+ oxygen.$

⇒ $2(1)+8$

⇒$10$

Thus one mole of Deuterium oxide has 10 neutrons.

The molecular weight of D₂O = $2(Mass of Deuterium)+mass of oxygen$

⇒$2(2)+16$

⇒$20$

Thus one mole, 20g, of Deuterium oxide has 10 neutrons.

Then the number of neutrons in 10g can be calculated as follows:

$20$$g$ → $10 neutrons$

$10g$ → $x$

On cross multiplication,

$x = \frac{(10)(10)}{20}$

⇒$\frac{100}{20} = 5$

Henceforth, the number of neutrons in 10g of D₂O is 5.