Which of the following statements is true about the relationship between atoms and molecules? A. Most atoms are bonded together to make a molecule. B. An atom can be seen by scientists, but a molecule cannot. C. Atoms and molecules are the same and have no differences.

I believe the answer is A. molecules are larger than atoms so they should be visible and atoms and molecules are indeed different

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons

answer: the value of enthalpy change will be -152.80 kj.

solution:

pressure = 1atm , temperature = = 298 k

given that pressure and temperature are same in both gases , the number of moles of both gases can be determined by the ideal gas equation.

according to reaction 3 moles no are reacting with 1 mol of ,then 0.49 mol of no will react with moles of ozone that is 0.16 moles of ozone. since, no is limiting reagent and is an excessive reagent.

enthalpy change for the reaction between the given volumes of the gases is :