Which example of mass has 1.2×1024 oxygen atoms?

1 mole of peroxide (h2o2)

1 mole of water (h2o)

2 moles of ammonia (nh3)

2 moles of hydrogen gas (h

1 mol of hydrogen peroxide (H₂O₂)  

Explanation:

Convert the number of oxygen atoms to moles

1 mol of H₂O₂ contains 2 mol of O atoms.

B is wrong. 1 mol of H₂O contains 1 mol of O atoms.

C and D are wrong. NH₃ and H₂ contain no O atoms.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

under a microscope, cancer cells may look very different from normal cells. they often have different sizes and some may be larger than normal while others are smaller. cancer cells are often abnormally shaped and the control centre of the cell (the nucleus) may have an abnormal appearance.

i think? ?