Apiece of sodium metal reacts completely with water as follows: 2na(s) + 2h₂o(l) 2naoh(aq) + h₂(g) the hydrogen gas generated is collected over water at 23.0°c. the volume of the gas is 397 ml measured at 1.013 atm. calculate the number of grams of sodium used in the reaction. (the vapor pressure of water at 23.0°c = 0.0277 atm.)

0.736g

Explanation:

Firstly, we can use the general gas equation to get the volume produced at s.t.p.

The form of the general gas equation used is :

P1V1/T1 = P2V2/T2

The values of each are given below :

P1 = (1.013 - 0.0277) = 0.9853atm.

This subtraction is because the gas was collected over water and hence there is bound to be contribution of water to the total pressure.

V1= 397ml

T1 = 23 + 273 = 296K

This is the conversion from celcius temperature scale to absolute temperature scale. This is the scale used in this kind of calculations.

T2 = standard temperature = 273k

P2 = standard pressure = 1atm.

V2 = ?

Substituting the values will yield:

(0.9853 × 397)/296 = (1 × V2)/273

Via calculations, V2 = 360.77ml

Now we know the volume produced at S.t.p

Secondly, we use a relation to get the number of moles yielded.

At s.t.p, 1 mole of a gas occupies a volume of 22,400ml.

If 1 mole occupies 22,400ml volume, x moles will occupy a volume of 360.77ml

Hence, the number of moles is obtained by dividing 360.77ml by 22,400ml = 0.016mole

Now, we go back to the reaction equation.

We can see that 2 moles of sodium metal yielded 1 mole of hydrogen gas.

Hence, y moles of sodium metal would have yielded 0.016mole of hydrogen gas.

Thus,y equals 2 × 0.016 = 0.032moles

Or we just simply say they have a mole ratio of 2 to 1.

Lastly, we can now get the mass of the sodium metal used in the reaction.

We use the relation as follows,

Mass of sodium metal used = number of moles of sodium metal × atomic mass of sodium metal

The atomic mass of sodium metal = 23

Hence, the mass used = 0.032 × 23 = 0.736g

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.

2b2t

explanation:

2b2t