Here, Molar mass of N2O4 = 92.02 g/mol
So, Number of molecules in 1 mole (92.02 g) = 6.023 * 10²³
Number of molecules in 76.3 g = 6.023 * 10²³ / 92.02 * 76.3
= 6.023 * 10²³ / 1.20
= 5 * 10²³
In short, Your Answer would be approx. 5 * 10²³ molecules
Hope this helps!
Answer:
It will float
Explanation:
Polystyrene is not dense and its light and full of air. It will float.
Answer:
Orbital
Explanation:
He developed the Rutherford model, which was the orbital model.
Answer:
a) 
b) NR
c) NR
d) 
e) NR
Explanation:
a) Nickel is more reactive than copper so the first one will displace the other:

b) Due to the higher reactivity the magnesium has compared to the zinc, the first will remain in solution and the second will reamin solid. So, NR.
c) No reaction occurs, gold is resistant to acid in normal conditions due to its characteristic as noble metal.
d) Chromium is more reactive than cobalt so the last one will be displaced:

e) Nothing happens, the reduction potencial of the hydrogen gas bubbled ins't enough to reduce the silver.