How many molecules of H2 are present in 7.5 grams of H2? How many H atoms?

The answer is 2.258 x 10^24 molecules are presented in 7.5 grams of H2.

Explanation:

I am going to use the chart that I attached to answer this question.

To convert grams to molecules we need to divide by the molar mass and multiply by 6.02 x 10^23, which is the value of a mole.

In this case the molar mass is 2 because the molar mass of H is 1 and we need to multiply by 2 to get the molar mass of 2 hydrogens.

Molar Mass = 1 x 2 = 2

Then, we need to divide the grams that we have by 2 to covert grams into moles. Finally, to convert moles into molecules we need to multiply the moles by 6.02 x 10^23.

7.5 grams / 2 = 3.75 moles

(3.75 moles)(6.02 x 10^23) = 2.258 x 10^24 molecules

Molecules are equal to atoms, so 2.258 x 10^24 molecules = 2.258 x 10^24 atoms

altitude, density, pressure

air gets less dense the higher the altitude and also the air pressure is less as altitude rises.

it is to be noted that an alpha particle is an helium nucleus. so it contains 2 protons 2 neutrons and has a mass number of 4. when alpha decay particles are ejected from the nucleus it gets transformed into an atom which has atomic number less than 2 and a mass number less than 4.

an equation that could represent alpha decay is radium 226 decay of alpha particle forms radon 222.

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