Question 3: Empirical and Molecular Formula (1 point) a. What is the difference between the empirical formula and the molecular formula? (.5 point)

b. How does one determine the molecular formula from the empirical formula? (.5 point)

Question 4: Percent Composition (3.5 points)

a. How is the percent composition by mass determined? (.5 point)

b. Determine the percent composition of each element in MgCl2. (1 point)

i. Magnesium (Mg): (.5 point)

ii. Chlorine (Cl): (.5 point)

c. Calculate the empirical formula from the given percent compositions.
82% nitrogen (N), 18% hydrogen (H) (2 points)

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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in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.

50.23 i believe is correct but don't quote me on that.