Molecular formula of sulfur trioxide is SO₃
Molar mass of SO₃ is - 32 + (16 x 3 ) = 80 g/mol
1 mol of any substance consists of 6.022 x 10²³ units. In 1 mol of SO₃ there are 6.022 x 10²³ molecules of SO₃
in 80 g of SO₃ - there are 6.022 x 10²³ molecules of SO₃
Therefore in 78 g of SO₃ - there are 6.022 x 10²³ /80 x 78 = 5.871 x 10²³ SO₃ molecules
<span>Because protons and neutrons are so much more massive than electrons, almost all of the atomic mass in any atom comes from the nucleus, which contains all of the neutrons and protons.</span>
In a heterogeneous mixture, you can clearly see the distinction between the different substances within the mixture. e.g. fruit salad, paella, nachos
in a homogeneous mixture, it is still made up of different substances, but there is no way of distinguishing between them just from appearances. they have the same uniform composition throughout. e.g. salt water; you know it is made of salt and water, but the salt is dissolved uniformly throughout that you cannot tell.
hope that helps :)
Answer:
Chilling the hydrogen peroxide solution
Explanation:
The MnO₂ is acting as a catalyst.
Chilling the hydrogen peroxide solution reduces the average kinetic energy of the H₂O₂ molecules.
Fewer of them will have enough kinetic energy to overcome the activation energy of the reaction. The rate will decrease.
A is wrong. Using a larger amount of solution does not increase the number of H₂O₂ molecules that can reach the surface of the catalyst per second. There is no effect on the rate.
B is wrong. Increasing the mass of the cube increases its surface area. More molecules of H₂O₂ can reach the surface of the catalyst per second. The rate increases.
D is wrong. Smashing the cube into pieces vastly increases the surface area, so the rate increases
