Question

M (Ca)=20г найти n (O^2)

Answer 1

20 г. Х моль
2Ca + O2 = 2CaO
n=2 моль. n=1 моль
М=40 г/моль
m=80 г
20 г Са. -. Х моль О2
80 г Са. -. 1 моль О2
n(O2)=20*1/80=0,25 моль

Answer 2

To find the number of moles of oxygen gas (O2) in the given sample, we first need to know the molar mass of oxygen. The molar mass of oxygen (O) is approximately 16.00 grams per mole (g/mol).

Now, we have the mass of calcium (Ca) in the sample, which is 20 grams (M(Ca) = 20g). However, we don't have any information about the total mass of the compound or the molecular formula of the compound. Without this information, we cannot directly calculate the number of moles of oxygen (n(O2)).

To calculate the number of moles of oxygen (n(O2)), we would need the mass of the oxygen present in the compound. If you can provide additional information about the compound or the total mass of the sample, I can help you further with the calculation.